Counting On and Back by 10s and 100s: Rainbow Castle

Across the moat at Rainbow Castle, a path of big stepping stones leads to the gate. Princess Ruby plays a game: every hop is worth 10 points, and every big leap is worth 100 points!

Remember: Counting by 10s changes the tens digit: 230, 240, 250. Counting by 100s changes the hundreds digit: 230, 330, 430. When the tens go past 9, the hundreds go up by one: 290 + 10 = 300.

Magic trick: Put your finger on the place that changes. For 10s it’s the tens, for 100s it’s the hundreds; the other digits stay still.