When practice is not mixed, the brain starts remembering the patterns. Alternatively, interleaved practice helps students discriminate between the different kinds of problems so they will be more likely to recognize the correct solution method for different problem types. Also with mixed practice, students grow comfortable seeing information presented in multiple and perhaps unexpected ways. When it comes time for the test, students are better equipped to analyze a problem and identify the appropriate procedure, and they are less likely to get stuck if the problem is presented to them in a less familiar format.