Use this worksheet to explain to your kids the concept of even and odd numbers. When there is an even number of objects in a group, all the objects can be paired in twos. However, when the number of objects falls on an odd number, all the objects cannot be paired, and one object will be left with no pair. In this printout, your students’ task is simple; find and check all the groups with an odd number of fish. Help your little ones count the fish in each group and figure out which ones are odd.