Curriculum › Math ›Grade 1

Grade 1 Math · Level 3, Place Value to 120

Build Teen Numbers

How the lesson starts: Build Teen Numbers

1. The duckling raft

   Quack, quack! Mama Duck has a little raft. It holds exactly 10 ducklings. Extra ducklings swim next to it. Let's build teen numbers with them!

2. 10 and some more

   Here is the full raft of 10. Now 4 more ducklings swim up. Count on from 10. 11, 12, 13, 14! 1 ten and 4 ones is 14.

3. Which blocks?

   Which blocks show 14? 1 rod and 4 cubes. Yes, that's 14! 4 rods and 1 cube is 41. 2 rods and 4 cubes is 24. Watch out! A teen number has just 1 rod.