Interleaving (Mixed Practice)

Mixing related problem types or skills during practice so learners must often select the appropriate approach, with effects that depend on task and schedule.

Interleaving mixes related categories, procedures, or skills across practice rather than completing a long block of each. It can require the learner to determine which approach fits the current case, instead of receiving that choice from the worksheet's order. Spacing and comparison between examples can also contribute to its effects.

Mixing is useful when the learning target includes discrimination and the learner has enough foundation to attempt the cases. Randomly alternating unrelated activities is not the same intervention. Effects vary across domains and schedules; initial guidance or blocked practice can remain helpful before mixing, and harder practice does not guarantee better transfer.

When to use it

When learners perform well in labeled blocks but cannot choose the right method in mixed or unfamiliar contexts.

How it can help

Mix cases that need discrimination after establishing enough foundation, then test delayed selection and execution.