While Professors Dunlosky and Willingham rated retrieval practice (part 1) and spaced practice (part 2) as highly effective methods for explicit learning, they also identified two other methods as moderately effective: interleaving practice and generating explanations.
Interleaving Practice
Interleaving practice is basically studying multiple topics or ideas all at once, rather than isolating them one by one. For example, if you are using interleaving practice in math, you may choose to teach addition and subtraction together, rather than apart. In comparison, blocked practice would require that you teach those concepts apart from each other, one at a time. The theory is that interleaving helps the brain see patterns, differences, and similarities between concepts. So it’s better able to create solutions and see the big picture whenever it is presented with a problem.
The Research
Doug Rohrer and Kelli Taylor at the University of South Florida conducted a study in 2007 comparing blocked practice and interleaving practice in learning math. College students were asked to memorize the formula for computing the volume of different geometric shapes. Students were divided into two groups where the first group used a blocked approach to learn the different formulas, learning and practicing each formula one at a time. The second group used interleaving practice and learned and practiced all of the formulas at the same time. The groups were then tested a week after their last practice sessions.
The blocked group performed much better than the interleaving group during practice sessions. On average, they got about 90% of their practice problems correct while the second group averaged about 60%. However, the interleaving group correctly answered three times more problems on the test a week later than did the group using blocked practice (63% vs. 20%).
Taylor and Rohrer also conducted a study in 2009 with 10-11 year olds that confirmed the benefits of interleaving in learning.
Here is a great article on interleaving and how you can use it in the classroom.
Limitations
Though existing studies show that interleaving provides great benefits to learning, there is still not enough research. A lot of the studies focus on math learning. In addition, as acknowledged by Taylor and Rohrer in their 2009 study, a lot of the experiments exploring interleaving practice have a design that pairs interleaving practice with spaced practice, which has been proven to greatly increase learning on its own. Though in reality, it is difficult to separate interleaving from spaced practice. So the studies are still helpful.
As a social studies teacher, I am more curious to explore how interleaving could work in the study of history. There are some great articles online that recommend studying different events in history based on one common theme at a time. I can see the potential in this, but I have reservations and questions about its practicality in daily classroom use since the subject of history just naturally deals with a lot of information.
Generating Explanations
The second method that Dunlosky and Willingham rated as moderately effective is generating explanations. It’s a method that requires students to look at information and come up with their own explanations about how or why things are the way they are. They should be constantly asking questions about the information they are learning. This method requires using new information to build upon existing knowledge.
The Research
Michael Presley and his colleagues at Western Ontario University conducted a study to explore the effectiveness of generating explanations. They gave three groups of adults three different types of sentences to learn. Group 1 read sentences that about topics that don’t seem to be related. For example, one of the sentences was “ The strong man carried a shovel.” Group 2 were given the same sentences, but each sentence provided an explanation. So for example, one of Group 2’s sentences was “The strong man carried a shovel to dig out heavy rocks.” Group 3 was given the same sentences as the first group but was also asked why they think the strong man carried the shovel. So they were forced to generate their own explanations. When the three groups were tested later, the group that was forced to come up with their own explanations scored about twice as much (75% correct) as the first two groups, who scored similarly to one another (about 35%).
Eileen Wood et al. (1993) conducted a similar study with preschoolers and children from grades 4-8. They found that generating explanations greatly benefited learning in children. They also found that children who had more prior knowledge benefited more from generating their own explanations than did their peers who had a less expansive knowledge base.
In the Classroom
I have definitely observed the benefits that generating explanations has on learning in my middle school social studies classes. I think it lends itself a lot more to social studies than interleaving. I’ve seen a drastic difference in my students’ comprehension and retention of information when I give them opportunities to explain and predict cause and effects and relationships between people and events. They are also more engaged which probably has a lot to do with the greater amount of learning that happens.
Some other useful facts about conscious, explicit learning that are helpful to keep in mind when designing your lessons
- The brain does not learn information verbatim. Instead, it takes out concepts and ideas from the words and sentences we come across and stores the ideas rather than the words.
- Our visual memory is stronger than our verbal memory. Pictures leave a much deeper and longer impression in our brains than do words.
- We learn much more effectively when we attach new learning to existing memory. This is why it’s very important to relate new information as much as possible to information that has already been learned in class or to things that students already know.
- The most effective factor for learning is motivation. It is very important for students not only to believe that they can learn whatever it is we are teaching them, but they also need to be motivated enough to overcome whatever challenges they’ll encounter in learning the information or skills.