Variety makes everything a little more fun and a little less boring, but it also enhances memory. When it’s time for your students to focus on practicing skills or reviewing material for mastery, mix the content rather than blocking the content. Blocking content involves concentrating on one type of skill, rather than practicing multiple skills together. But when practice lessons intermingle assorted skills, the students have to engage in thinking that goes deeper* than activities that focus on only one skill. Working with varied content requires students to mind the details, comprehend similarities and differences, as well as compare and contrast content. In turn, students remember content better and perform better.
For example, math assignments should be a mixture of different types of problems rather than a block of the same type. Practice exercises in grammar should involve identifying more than one part of speech, rather than only adverbs. PE class should drill more than one volleyball technic daily for several days, rather than focusing one class period on a single skill and then changing to a different single skill the next day. If students need to memorize significant material in history, practice the need-to-know material along with newly-learned material; this will give them an opportunity to make comparisons and think through the details more precisely. This method can be applied to skills training in all subjects, such as humanities, science, foreign language, and music.
Students may be tempted to think that they are not progressing, because mastery in a single skill is developed at a slower pace. However, they will be mastering more than one skill at a time, and in the end, they will have learned all of these skills with a much higher level of proficiency. Don’t confuse this practice method with teaching at the concrete stage. When teaching a new concept for the first time, you may have to devote more time to ensure understanding. But when it’s time to start practicing for mastery, mix it up.
*For more reading on this topic, Chapter 5 (“The Benefits of Interleaved Practice” by Sean H. K. Kang) in From the Laboratory to the Classroom thoroughly explains the research behind this teaching strategy.