Make It Stick
Make It Stick: The Science of Successful Learning is an excellent introduction into the many areas of cognitive science that sheds light on how we best learn. The book is split into chapters each of which focuses on a particular area of this science. However, much of this information is given following the advice of the book itself, and it is revisited regularly. It is also told through stories of individuals who have learnt to learn successfully across a huge range of experiences. These stories give the reader an excellent real world context upon which to pin the science which is then discussed.
Written by a writer and two cognitive psychology professors, this book is unique in its approach to helping people understand the science of learning. It covers both the scientific basis but also is written in a way that connects with the reader in a way that academic work rarely does.
Below I will briefly summarise the main points from each chapter. You can find many more resources on the book which have been collated by Pooja K Agarwal of retreivalpractice.org here. There is another review of the book here.
Chapter 1 - Learning is Misunderstood
This chapter starts the journey in to the science of how we learn introducing us to many concepts which will be returned to in later chapters. First, the definition of learning is given as "acquiring knowledge and skills and having them readily available from memory so you can make sense of future problems and opportunities". This is broken down into three key points:
"learning requires memory, so what we've learned is still there later when we need it"
"we need to keep learning and remembering all our lives"
"learning is an acquired skill, and the most effective strategies are often counterintuitive"
Pages 3 through 7 briefly introduce the ideas that make up the rest of the book:
To make learning more durable it needs to be effortful. "Learning that's easy is like writing in the sand, here today and gone tomorrow". Unfortunately we are not very good at judging when we are learning well, and often people will use strategies such as rereading text and massed practice (practicing a skill repeatedly until a feeling of fluency) which are actually the least productive ways of learning.
Retrieval practice - the idea of recalling information from memory - is the most effective learning strategy. There are many forms of retrieval practice, and the act of retrieving "strengthens the memory and interrupts forgetting". Testing ourselves ( a specific type of retrieval) helps us calibrate our knowledge and understanding, and helps prevent us from falling prey to illusions of knowledge.
Spacing out study by leaving time between study sessions, or interleaving study of different ideas both create a more effortful learning experience, and although this feels more difficult, it leads to longer lasting learning. Interleaving, or the use of varied problems, helps us develop the ability to differentiate between similar problems, and hence choose the most appropriate response.
Attempting to solve problems before being shown how to do it helps us learn better, even when we get the answer wrong.
Fitting instruction to a student's learning style is not backed by any research to suggest it helps learning.
All learning is built upon our prior knowledge, and certain knowledge is required to be able to progress further in any subject of learning. There is not shortcut to learning the basics before being able to proceed.
By connecting new knowledge to existing knowledge through acts of elaboration we can essentially give ourselves limitless potential to learn. Finding the larger context of our new learning also helps us to fit it in within our prior knowledge structures. The best learners are those that are able to extract the key information from new material, and connect this to prior knowledge and the bigger picture.
We are all capable of improving our own learning. Although there is an element of genetic ability, our brains change every time we learn something new, and we can control how "smart" we are by using the strategies listed. Understanding this enables us to see failures not as an inherent part of our genetic ability, but as an opportunity to learn and develop.
The next part of this chapter looks in a bit more depth at the idea that rereading and massed practice do not help learning. But we all know that these two methods of study are among the most popular for students, so why is that the case? Largely because they create an "illusion of knowing" where we develop a sense of "fluency" with the material from seeing it regularly in a short period. This fluency is short lived, however. In expanding upon this, the authors quote Donald Rumsfeld in 2002: "There are known knowns; there are things we know that we know. There are known unknowns; that is to say, there are things that we now know we don’t know. But there are also unknown unknowns - there are things we do not know we don't know". This is used as an example of why students should quiz themselves, to identify the unknown unknowns.
Now the authors briefly attack the idea that we should aim for creativity over knowledge, and the fact that this is nonsense as creativity requires a strong background knowledge. One can only be creative if you have the knowledge to create with. They make the case that a lot of people in education keep going on about creativity as the most important, but that when going for surgery you want your doctor to have a lot of knowledge about what they are doing. It is not a case of knowledge versus creativity, however, but rather that knowledge is required to be creative. This reminded me of a blog post I recently read.
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/11/05/reading-of-make-it-stick-by-brown-roediger-and-mcdaniel-part-1/
Chapter 2 - To Learn, Retrieve
Chapter 2 starts with the story of Mike Ebersold, a neurosurgeon, who recounts a particular incident when he had to operate to remove a bullet from somebody's brain. It was a messy case, where operating to remove the bullet was essential, but in doing so there was a high chance of severe blood loss due to the location of the bullet next to a vein. During surgery Mike had to deal with this problem and due to his practice and experience "it becomes reflex, mechanical". Mike was able to rely on his knowledge and skill to deal with the situation, and the patient survived with only minor loss of peripheral vision.
Mike explains the process of getting to this point of mechanical reflex through reflecting on previous surgeries, practicing in his mind and retrieving the skill on a regular interval. The process of "reflection can involve several cognitive activities that lead to stronger learning: retrieving knowledge and earlier training from memory, connecting these to new experiences, and visualizing and mentally rehearsing what you might do differently next time".
The testing effect, or retrieval-practice effect, is the name that psychologists give to the phenomena whereby we produce longer lasting learning through retrieving information than we do through reexposure. To be effective retrieval should be spaced out to create the need for cognitive effort, rather than mindless recitation. But the testing effect has a bad name, as many people respond to the name in a negative way. The New York Times reported a study where students who took a test after reading a passage of text recalled 50% more a week later than those who did not take the test. These results have been shown over and over again in empirical research (detailed in pages 30-32), and yet the response is often along the lines of we don't need students to remember facts, we need students to be able to think.
However, "pitting the learning of basic knowledge against the development of creative thinking is a false choice. Both need to be cultivated. The stronger one's knowledge about the subject at hand, the more nuanced one's creativity can be in addressing a new problem."
The ideal scenario from the research is to have multiple testing sessions throughout the learning process, and these should be spaced out. From experience in student reactions, the story of one teacher tells us that retrieval quizzes work best when they are not a surprise to students, but they know in advance they are going to happen. Another school was involved in an experiment set up by the authors of the book to try to replicate the results of experiments from the lab in a classroom setting.
"The results were compelling: The kids scored a full grade level higher on the material that had been quizzed than on the material that had not been quizzed. Moreover, test results for the material that had been reviewed as statements of fact but not quizzed were no better than those for the nonreviewed material."
Feedback on retrieval helps to improve retention even further, and there is some research to suggest that delaying feedback could be beneficial, with the suggestion as to why this might be the case being that it creates some spacing where students have to again think about what they did when they get the feedback.
But is testing just a way to speed up rote learning of material? Not at all. Research suggests that, compared to rereading, testing helps improve transfer of knowledge, and it helps retrieve related but untested material. Students even seem to prefer it, with courses where regular testing was present, students tended to rate them more favourably. "Students who have been quizzed have a double advantage over those who have not: a more accurate sense of what they know and don't know, and the strengthening of learning that accrues from retrieval practice."
The Takeaway at the end of this chapter is particularly good, and covers all the main points from the chapter in a succinct way (it is definitely worth a read).
I talk in depth about how I now do my weekly quizzes in this blog post, but from a recent survey I did with my students, all of them said they felt that weekly quizzes was beneficial to their learning, mostly in helping them identify what they do not know. The reflection sheet I use has also got students thinking a little more about the questions they got wrong and how they can improve in future.
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/11/11/reading-of-make-it-stick-by-brown-roediger-and-mcdaniel-chapter-2/
Chapter 3 - Mix Up Your Practice
This chapter starts with a brief overview of a famous test.
"A group of eight-year-olds practiced tossing beanbags into buckets in gym class. Half of the kids tossed into a bucket three feet away. The other half mixed it up by tossing into buckets two feet away and four feet away. After twelve weeks of this they were all tested on tossing into a three-foot bucket. The kids who did the best by far were those who'd practiced on two- and four-foot buckets but never on three-foot buckets."
It is a well held myth that we learn better by massing practice. Doing this "burns a skill into memory". It is true that this will lead to a quicker feeling of mastery over knowledge or a skill, but this is only part of the story. Does the learning stick? Practice is essential to learning and memory, but practice that is spaced, interleaved or varied is far more likely to lead to learning that sticks. But this is more effortful, and learning feels slower using these methods of practice. Even after participants in studies have seen the effects of spaced learning, the still believe they learned better when they used massed practice.
Spaced practice is the idea of doing the same studying but instead of doing 4 hours in one block, do 1 hour a day for 4 days. In order to learn new things our brains need time to consolidate the new information, which makes connections between the new information and prior knowledge. This takes time, and sleep plays an important role in this process, so spacing out learning over a few days or weeks is best. The optimal timing is when you are starting to forget, so retrieval is effortful.
Interleaved practice is mixing up practice of two or more skills. The example given is of students learning the formulae for the volumes of 5 different shapes. One group practices each formula one at a time (10 questions on sphere, then 10 questions on cone, etc). The other group practiced the exact same questions but mixed up (interleaved). The results were amazing: during the practice the massed group averaged 89% whereas the interleaved group averaged 60% correct. But in a test a week later, the massed group got only 20% and the interleaved group got 63%. So interleaving actually improved learning over time!
Varied practice is when different, but related, tasks are used in study compared to the test. The beanbag example from the start of the chapter is given as an example of this, though it is recognised that this is learning motor skills rather than cognitive skills. There is some early research which shows similar outcomes or varied practice for cognitive skills.
One of the main benefits of interleaved and varied practice is the idea that it helps to develop discrimination skills, or the ability to decide which particular skill to use for a given circumstance. Two examples are given for this, the first of which is a famous study around deciding which painter painted certain paintings. The massed group were shown paintings by one painter at a time, and the interleaved group were shown paintings by different painters in a mixed order. Once again, the interleaved group were much better able to match the paintings they had seen to the correct painter in a later test. But more interestingly, they were also much better at assigning paintings that they had never seen before to the correct painter. As the authors say "the commonalities among one painter's works that the students learned through massed practice proved less useful than the differences between the works of multiple painters that the students learned through interleaving". Similar results have been found in a study on discriminating between different species of birds.
But it is important to remember that we learn by experience, and doing something is the best practice for doing it better next time. But experience itself is not enough, we have to learn from it, and to do this we need to add some extra elements to our experiences. First we need to reflect (linked to ideas from the neurosurgeon Mike from Chapter 2), do mental rehearsal and elaboration. Asking ourselves "what worked", "what didn't work" and "what would I do differently next time" are three key questions in the process of reflecting and learning from our experiences.
These ideas are linked to two examples, one from another doctor trainer and one from a football coach.
Avoiding massed practice is the key takeaway from this chapter, and for our students that is avoiding cramming for an exam. Although it might enable them to pass a particular test, it is not going to be beneficial for learning in the long run. And since knowledge is built on prior knowledge, we need to learn cumulatively as we progress through life. The other benefits of interleaving and varied practice are the improved discrimination skills that they develop. And the further dangers of massed practice are the trap of feeling fluent and stopping practice (similar to rereading to an extent).
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/11/18/summarized-reading-of-make-it-stick-part-3-mix-up-your-practice/
Chapter 4 - Embrace Difficulties
We start this chapter with the story of Mia, and how she learned to jump out of a plane as a US Marine. The method of learning this skill is that the difficulty is slowly ramped up. As you become confident in falling to the ground, the instructor makes you start jumping from 50 cm. Then as you start to feel confident, it goes up to 3 m, attached to a zip line. The increase in difficulty of the tasks, and the spacing between attempts, helps consolidate the new learning until you can successfully jump out of a plane. Difficulties such as these are known as desirable difficulties.
The authors then discuss how learning works in our brains.
Encoding - this is the process where our brain takes information from the environment and makes it usable in our brain. But these ideas are fleeting. They occupy the working memory. Without the next stage, this learning will not stick.
Consolidation - this is the process of strengthening the long term memory of our experiences and learning. This is when the new information is reorganised and sorted into meaningful chunks. This takes hours, possibly longer. Prior knowledge is vital to be able to consolidate new learning, as we attach new knowledge to stuff we already know.
"the process of learning something often starts out feeling disorganized and unwieldy; the most important aspects are not always salient. Consolidation helps organize and solidify learning, and, notably, so does retrieval after a lapse of some time, because the act of retrieving a memory from long-term storage can both strengthen the memory traces and at the same time make them modifiable again, enabling them, for example, to connect to more recent learning."
Retrieval - creating retrieval cues is also very important so we can retrieve things we have learnt. You need to regularly retrieve knowledge to be able to remember it.
The more we know the more retrieval cues we can create for new learning. But we also need to forget cues at times, to be replaced by updated, corrected or related concepts. When learning French, you can get confused with similar words in Italian. But we do not forget things we have consolidated into long term memory. What we see as forgetting is actually just more difficult to retrieve. We may not be able to recall our childhood phone number, but if somebody showed us a list of 10 phone numbers, we would be able to identify it easily. The memory is still there, just not retrievable.
But easier is not better when it comes to learning. In fact, "the easier knowledge or a skill is for you to retrieve, the less your retrieval practice will benefit your retention of it". The more effort you have to make to retrieve something, then the better you will learn it.
Making learning more difficult through spacing, interleaving and variation actually make long term retention much stronger. But even when we see this for ourselves, we will still choose to do the easier methods (massed practice).
The next section is titled How Effort Helps, and lists these ideas:
Reconsolidating Memory
Creating Mental Models
Broadening Mastery
Fostering Conceptual Learning
Improving Versatility
Priming the Mind for Learning
"With enough effortful practice, a complex set of interrelated ideas or a sequence of motor skills fuse into a meaningful whole, forming a mental model somewhat akin to a "brain app"."
An interesting study is quoted that shows that if you read a text that is slightly out of focus, you will remember more than reading the same text in a normal easily readable font. Similarly, when letters are left out of words, reading is slowed down, but retention is increased. These are other examples of desirable difficulties (as long as the difficulty does not make it impossible to decipher meaning).
A useful strategy for teachers to use is the idea of generation. This is the desirable difficulty where you attempt to solve a problem without being told how to do it. By doing this students will remember the solution better, even if they get it wrong on their attempt.
Another one that we as teachers can make use of is getting students to reflect on their learning, which incorporates retrieval, elaboration and generation.
Since learning is better when it is effortful, clearly making mistakes is an important part of the learning process. Reflecting on mistakes leads to better retention. On the other hand, a fear of failure, or making mistakes, can also lead to anxiety which occupies valuable working memory space, leaving less to be able to think.
But some difficulties are not desirable. Not having the required prior knowledge to solve a problem this would be an example of an undesirable difficulty, as the student has no chance of being successful, and nothing to pin the new learning to. However there is little research to say what the undesirable difficulties are. Any difficulties that cannot be overcome are undesirable. Overloading working memory through people talking to you whilst you are trying to concentrate is clearly undesirable.
The big points in this chapter are to make learning a little bit difficult for our students, but in the right way. As Willingham states, "Memory is the residue of thought" so we should be trying to get students think hard about the material we want them to remember.
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/11/26/summarized-reading-of-make-it-stick-chapters-4-embracing-difficulties/
Chapter 5 - Avoid Illusions of Knowing
This chapter is all about how we are pretty bad at knowing when we are making a bad call, and that there are a lot of ways that our brain can trick us into thinking something that is not right. One sign of expertise in an area is that we are more able to spot our own errors in judgement. But that doesn't mean we aren't making the same errors in other areas of our lives!
Our brain works on two separate systems, as described by Daniel Kahneman in Thinking, Fast and Slow. The first is System 1 which is the automatic response system, the reflexes that we have developed through experience. The second is System 2 which is the controlled thinking system, which is slower. This system is also used to train our System 1 responses. System 1 is susceptible to illusion, and we often need to rely on System 2 to manage these. Several examples are given for when pilots "feel" like everything is right (System 1), but the instruments tell them something is wrong (System 2).
Human memory is not like a computer's memory. Our memories are subject to being distorted, as people interpret things differently based on their prior knowledge. We also forget bits of stories and our brain fills them in with things that seem consistent, but might not be correct.
When asked to imagine something, we are more likely to later remember that it actually happened. Being asked to imagine what breaking a window with your hand would feel like can lead you to later recall that this actually happened.
We are all susceptible to suggestion and interference of memories, and legal cases prevent these from being a problem by not allowing leading questions. Interference happens when two memories get mixed up.
The curse of knowledge is our tendency to be unaware of how hard it is to learn something we already know. The hindsight bias is when we think we always knew something after we have been told it, even though we couldn’t recall it. We have already talked about the illusion of fluency that can be created through massed practice or rereading. We normally assume everybody will agree with our beliefs and have the same beliefs as us.
"As you get more expert in complex areas, your models in those areas grow more complex, and the component steps that compose them fade into the background of memory (the curse of knowledge)"
The Dunning-Kruger effect is when "incompetent people overestimate their own competence", which is believed to be due to the lack of knowledge they have in that area.
We are all susceptible to these illusions, and the only way to overcome them is to do regular check ups on our thinking. The most effective tool we have for doing this is to test ourselves regularly. We can also do this by working alongside a more expert person, who can act as an external checker.
I have blogged about the Dunning-Kruger Effect and Curse of Knowledge before. But as teachers we also need to be aware of how students remember our classes and the content we teach. The likelihood is that in a class of 20 students, no two will remember the previous lesson in the same way. But if we can focus attention to the key points, hopefully they will stick with all students.
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/12/02/summarized-reading-of-make-it-stick-chapters-5-avoid-illusions-of-knowing/
Chapter 6 - Get Beyond Learning Styles
This chapter starts with the amazing story of Bruce, who, from a very young age, took control of his own learning, jumping from idea to idea, and learning all the way. This introduces us to the idea that we are all different, but that some differences seems to make a bigger difference in how we learn.
The saying "Whether you think you can or you think you can't, you're right" is introduced, and a teaser into the work of Carol Dweck (explored more in Chapter 7). The ability to abstract underlying principles is important for learning. Whether we are a visual or auditory learner is not.
Some difficulties that we face are not desirable. If we cannot decipher words when reading a text this gets in the way of understanding the text, and conditions like dyslexia can cause this. But you can learn to get past these difficulties over time, and with certain strategies. In developing these strategies is it possible that those with dyslexia actually have to become more creative?
Next the authors tackle the big one: Learning Styles. They concede that most of us do have preferred learning styles (though they do point out there are more than 70 different learning styles theories, each with a different set of styles), but that there is no evidence that we learn better through our preferred learning style. In fact, the mode of instruction should be matched to the content being taught (e.g. geometry is a visual subject, poetry is an auditory subject). When this is done, all students learn better, no matter their preferred learning style.
The concept of intelligence clearly makes a difference in how well we learn, but what is intelligence? Recently the idea that intelligence is fixed from birth has been challenged, and it is now generally accepted that intelligence can change through hard work. And the work of Howard Gardner and Robert J. Sternberg on different types of intelligences allows us to think about and classify the differences we see in individuals.
This leads to an idea called Dynamic Testing:
A test of some kind show me where I come up short in knowledge or skill
I dedicate myself to becoming more competent, using reflection, practice, spacing, and the other techniques of effective learning
I test myself again, paying attention to what works better now but also, and especially, to where I still need more work.
This process is designed to develop expertise in a particular area of knowledge or skill, and as teachers this is what we do when we get students to reflect on their performance in a test or quiz.
One way we do seem to differ in the way we learn is in how we build structures in our brains. In particular, some people are very good at narrowing in on the main idea, whereas others get distracted by the surface details. Another is the way that some people learn from general rules whilst others make use of examples. The example learners tend to try to memorize examples to apply, whereas rule learners can understand the connections. “However, example learners may improve at extracting underlying rules when they are asked to compare two different examples rather than focus on studying one example at a time."
The takeaways from this chapter are nicely summarised by the following subheadings:
Be the one in charge
Embrace the notion of successful intelligence
Adopt active learning strategies
Distill the underlying principles; build the structure
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/12/03/summarized-reading-of-make-it-stick-chapter-6-get-beyond-learning-styles/
Chapter 7 - Increase Your Abilities
This is a big chapter which covers some really important points. It starts by discussing the famous marshmallow test.
"The marshmallow study is sublime in its simplicity and as a metaphor for life. We are born with the gift of our genes, but to a surprising degree our success is also determined by focus and self-discipline, which are the offspring of motivation and one's sense of personal empowerment."
A short section on neuroplasticity explains some of the biology in how our brains can change readily, and are continually changing throughout our lives. Extreme examples are when people lose half their brain due to injury, and the remaining half "reprograms" itself to make up for this.
So can we increase our IQ? Do brain training games work? There appear to be ways to improve our IQ (the example of pregnant women taking dietary supplements which increased their IQ is particularly interesting). But brain training games do not appear to improve our overall IQ. "The brain is not a muscle, so strengthening one skill does not automatically strengthen others." In general, it appears that we cannot improve IQ by any meaningful amount, but what we can do is "amp up the performance of the intelligence I've already got".
Three ways that have been shown to do this are then explored in more depth.
Growth Mindset is the idea developed by Carol Dweck that if you believe that intellectual abilities are not fixed then you will approach learning in a different (better) way. If, on the other hand, you believe that intelligence is fixed, then you will not push yourself to learn the most you can. Students with a Fixed Mindset tend to focus on performance, always aiming to validate their ability or intelligence. In this mindset, effort is seen as a bad thing, as having to work hard means you have a low intelligence/ability. You will not see the need to practise. And you definitely do not want to fail, so you choose challenges that you are confident you can achieve. Students with a Growth Mindset, however, focus on learning, and aim to get better at each stage. In this mindset, effort is necessary to improve, and you will practise frequently. Failures and setbacks are seen as opportunities to improve in the future, and you will challenge and push yourself. The interesting point is raised that those in the lowest rungs of society have so many challenges to overcome that encountering success is rare. On the other hand, the kids who have everything handed to them on a platter, and are constantly told they are smart or amazing, also never get the opportunities to fail and develop the resilience required to become great learners.
Deliberate Practice is a phrase coined by Anders Ericsson to describe the way in which experts in a field slowly develop increasingly complex mental models. Deliberate Practice is not just experience, but actively seeking to improve through "striving, failure, problem solving, and renewed attempts". Deliberate practice is difficult, and for most it requires a coach or trainer to keep them on track. It takes an average of over ten thousand hours, or ten years, to develop the skills and knowledge of expertise in a field. Much of this time is spent in isolation, working on the skills using the model of deliberate practice.
Memory Cues, such as mnemonic devices and memory palaces are discussed in detail, linking back to the story of James shared earlier in the chapter, who complete in the World Memory Competition.
"It comes down to the simple but no less profound truth that effortful learning changes the brain, building new connections and capability. This single fact - that our intellectual abilities are not fixed from birth but are, to a considerable degree, ours to shape - is a resounding answer to the nagging voice that too often asks us 'Why bother?' We make the effort because the effort itself extends the boundaries of our abilities. What we do shapes who we become and what we're capable of doing […] And it comes down to the simple fact that the path to complex mastery or expert performance does not necessarily start from exceptional genes, but it most certainly entails self-discipline, grit, and persistence"
I recently blogged about a paper written by Dweck on Growth Mindset in relation to the praise we give as teachers. The work of Anders Ericsson on Deliberate Practice is high up on my list of things to check out as well, and this provided a nice little introduction. The 10,000 hours means that students are unlikely to become experts in any subject they study at school until well after they leave us, especially since most of the practice they do is not necessarily of the best type. Again, reflecting on their performance is important, and this is something which keeps appearing, and possibly something we should all put more attention on developing within our students.
As a side note to Deliberate Practice, this also makes me think about our CPD model, and how we, as teachers, can engage in this high level practice to improve how we teach.
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/12/04/summarized-reading-of-make-it-stick-chapter-6-increase-your-abilities/
Chapter 8 - Make It Stick
The last chapter lists a series of tips for different categories of people. In each tip the authors explain what it means, how to use it, why it feels difficult, etc.
Learning Tips for Students
Practice Retrieving New Learning from Memory
Space Out Your Retrieval Practice
Interleave the Study of Different Problem Types
Elaborate on the Meaning of New Learning
Generate Answers to Problems Before Being Shown the Solution
Reflect on what you did and what you would do differently next time
Calibrate your learning, and Check What You Know
Use Mnemonic Devices to help organise new learning
Tips for Teachers
Explain to Students How Learning Works
Teach Students How to Study
Create Desirable Difficulties in the Classroom
Be Transparent
Chapter Summary - https://themillioninmyhead.wordpress.com/2014/12/09/summary-of-make-it-stick-chapter-8-make-it-stick-for-students/