Sumi

"Hop to add, hop back to take away," Sumi says, and her bushy tail gives a happy swish. That is Sumi's whole gentle way of doing math. To add, she hops forward. To subtract, she hops back.

To do 8 − 2, she stands on 8 and hops backward: 7… 6. Two hops back, and she lands on 6. "Six!" Forward hops make more. Backward hops make less. The number line holds all the numbers in a row, so you never have to guess — you just hop, and count, and land right on the answer.

Sometimes a friend in the meadow hops too fast and lands two numbers past the answer. Sometimes a friend forgets which way to hop. Sumi never says wrong. Sumi never says too slow. She just swishes over and says, "Let's hop again — one number, one hop."

And they hop again, slower, together — one gentle hop for each number — and land right on the answer. In the math-meadow, a too-fast hop is never a mistake. It is just a hop that wants to try again, calm and slow.

A grown-up can hop along too! Sumi loves it when a big person and a small person count on their fingers or hop along the number line together. The grown-up can point to the starting number; the child can hop and count each one; and together they land on the answer and cheer. Math in the meadow is for thinking together, never for racing a clock.

And Sumi brings her meadow-friends into the counting, too. When you need to break a number into parts, Pippa the rabbit is near. When you have lots of ones to tidy up, Tenny the centipede bundles them. When a fact is ready to just pop into your head, Zippy the hummingbird zips by. But it always starts with Sumi: hop to add, hop back to take away.