Flashcards are a popular study tool that allow students to self-test and identify weaknesses. However, flashcards alone don't encourage deep understanding. This document provides a strategy for using two stacks of flashcards - one with concepts and one with instructions - to interact with concepts in new ways and improve understanding beyond memorization. The key is to randomly select a concept card and corresponding instruction card, such as describing a concept without its definition, and verbally responding to help solidify learning. This flashcard strategy can be used across various subjects.