Lesson 11-1

LET'S INVESTIGATE Make Teen Numbers

For more help with this lesson, view the Another Look Video.

MATH HELP AT HOME

Sample Additional Practice Exercise 1

How many cubes do you see? Complete the sentence to describe the number of cubes shown. Tell what you notice about the two groups of ones.

Train of 10 connected cubes. Train of 4 separated cubes. 10 and 4 is 14.

There are 10 connected cubes and 4 separated cubes. There are 10 ones and 4 more ones which is 14 altogether.

HOME ACTIVITY

Teen Groups

MATERIALS

Buttons or small objects

ACTIVITY

Use buttons or other small objects to show 13 as a group of 10 and some ones. Ask your child to describe the objects with the sentence “10 and 3 is 13.” Repeat with other numbers 11–19 and ask your child to complete the sentence “10 and _____ is _____.”