These are mini war cards with place value numbers on them that are no larger then in the ten thousands place value. Students play the game of war with them using place value as the determining factor as to who will take the cards and ultimately win the game.
These cards will enforce the idea of comparing numbers up to the ten thousands place value.
This skill is usually introduced in 3rd grade (in CA) and can be used for 4th and 5th graders as review.
Hope you and your students will enjoy a game of war!