Knowing how to take good notes is a skill that needs to be explicitly taught. Students (especially middle school students) do not naturally know how to take good notes that they can learn and study from.
I developed this note taking guide in a Cornell style so students have a structured way of keeping track of their vocabulary, thoughts, and mathematical ideas as they work through the problems in the Connected Mathematics series.
Accentuate the Negative Note Taking Guide - Investigation 2 (PDF)
Topic: Multiplying and Dividing Integers