Flash cards are a simple yet versatile teaching tool for young learners and lower level adult classes. They can be used to present, practice, and recycle vocabulary through various memory, drilling, identification, and movement activities. Teachers can buy pre-made flash cards, make their own, or have students create cards to reinforce lexical sets introduced in class. Common games include having students memorize and recall cards, play matching games in small groups, pass cards around in a circle while identifying them, and incorporate cards into movement games like Simon Says.