Mixed practice: choose the method before you solve

The heading should not choose the method for you

A worksheet headed “Area” gives away part of the task before a learner reads the first question. In a mixed set, the learner has another decision to make: what is this problem asking, and which method fits? That decision deserves attention alongside accurate calculation.

For your next revision session, try a small set of familiar problem types without naming the method above each question. Keep the instructions clear. The aim is not to trick the learner or remove useful support; it is to make the choice of method visible.

What the research found—and what it did not

Rohrer, Dedrick and Stershic’s 2015 classroom study analysed 126 seventh-grade students at one Florida school. Students practised graph and slope problems using interleaved or blocked schedules, with the skills counterbalanced across classes. The problems were the same, but their arrangement differed over three months. After a common review, tests given one or 30 days later favoured interleaved practice.

The result has important boundaries. Students in the participating classes had passed the previous year’s state maths test. New test questions used the same formats as practice, so the study does not establish transfer to very different problems. Interleaving also spaced practice across assignments: the benefit cannot be attributed solely to mixing. This was not a test of SASHA or a guarantee for every learner.

A small revision routine to try

The following is a practical adaptation, not the study’s tested protocol. Choose two or three methods the learner has already been taught. For example, a teacher might select familiar questions about a rectangle’s area, its perimeter and a missing side length. Check first that the wording and diagrams are accessible.

For a fictional example, one question could ask how much ribbon is needed around a rectangular card; another could ask how much paper covers its front. Ask the learner what each measurement represents before discussing a formula. Keep the numbers straightforward at first so that a difficult calculation does not hide a misunderstanding about the quantity being measured.

Before calculating, ask: “What do I need to find? Which method would I use, and what in the question tells me that?” A short spoken explanation, a sketch or an annotated example can make the choice visible. Avoid turning the explanation into an extra writing burden.

Let the learner complete the attempt, then check both the choice and the calculation. If the method was appropriate but an arithmetic step went wrong, name that specifically. If the method did not fit, compare the question with a nearby example and identify the detail that changes the approach.

Finish with one fresh question to try independently. Keep a brief note: “Chose area correctly; still mixed up perimeter and missing-side questions.” That is more useful for planning support than simply recording a total score.

Keep support, and adjust the difficulty

Do not make a learner guess at methods they have never been taught. If every question stalls, return to instruction and a clear example before trying a smaller mixed set. A parent or tutor can ask the teacher which methods are ready for revision rather than introducing a competing approach.

Mixing and spacing are different planning choices: one concerns which problem types appear together; the other concerns when practice returns. You can plan a short mixed set now and revisit it later. Judge the next attempt on its reasoning and accuracy, not on how quickly the page gets finished.

A question to ask of learning tools

When evaluating a learning tool, ask whether its demonstration helps you inspect how a learner chose a method, not only whether the final answer was correct. Can you tell when a hint supplied the choice? These are evaluation questions, not claims about available SASHA features.

The practical takeaway: give learners a manageable opportunity to choose, explain and check a method. Use what you notice to decide what to teach next.