The Ocean City Sharks swim team—Gill, Fin, Stripes, Tiny, and the hammerhead twins, Flip and Flap—really want to go the state swim meet, but they're short on funds. If they can swim 75 laps over the next four days, the local newspaper will sponsor them. The first day they swim a total of 14 laps (75 - 14 = 61). The next day they do a little better with 17 laps (61-17 = 44) But will they make their goal?

Learning to subtract 2-digit numbers with and without regrouping prepares children for subtracting larger numbers.

MathStart is an award-winning series by Stuart J. Murphy that teaches math through stories and visual models. Young readers find the stories engaging and relatable, because each story revolves around practical applications of the math concept being presented and features lively art from top-notch illustrators.

Charts and other visual representations help children understand how the math works and promote deeper comprehension. This unique combination of stories, illustrations, and visual models helps teachers and parents in the teaching of math and provides all children with the opportunity to succeed.

The 63-book series is divided into three levels with 21 books in each. The math concepts taught in MathStart books conform to state and national standards. Level 1 is Pre-K–Kindergarten; Level 2 is Grades 1–3; Level 3 is Grades 2–4. The series follows math topics across grades so there is a foundational path to learning that runs through the levels.