In this classic memory game (on pages 37-45 of PDF), learners turn over tiles to reveal images on the back. They turn over two tiles at a time, and try to remember past tiles so they can find matching pairs. The tiles provided with this lesson plan are not identical pairs, but numerals and images of certain numbers of fruits, abstract shapes and objects incorporating those shapes, or adult and baby animals. Younger learners can play the game alone and just focus on matching, while older students can play against a partner. Extensions include making cards for other science subjects, or language skills.