Skip counting is a useful skill if you need to count sets of objects, such as pairs of shoes, gloves, the wheels on a tricycle, or even money. Counting on in twos, threes, fives and tens is easy, if ...

An insomniac girl named Clarissa tries counting sheep to fall sleep, but it has the opposite effect: “A loud baa made her open her eyes, and to her surprise, she saw ten sheep in her room.” Counting ...