Math Background

Lesson: Number Concepts
Developing the Concept

When children demonstrate understanding of numbers 0-10, they will be ready to work with larger numbers. Have children work with partners.

Materials: beans, 3” x 3” squares of paper, Learning Tools 8 and 9 for number cards 10 to 20, writing paper and pencils

Preparation: Give pairs of children 11 to 20 beans and 2 squares of paper.

  • Ask: How can we find out how many beans you have?
  • After children say they can count the beans, ask them to make a group of 10 beans and place them on a square of paper.
  • Ask: How many groups of 10 did you make?
    When children answer “1,” write the number.
  • Ask: After you made a group of 10 beans, how many more beans do you have?
    After children say the number, write the second numeral next to the 1, and identify the new number. Say it together. Then have children write the new number themselves. Reinforce place value by saying, One group of 10 and 2 more. The number is 12.
  • Repeat with other examples. Reinforce the idea that children make one group of 10 and then count the extra beans. As children gain understanding, you can continue with numbers to 29.
  • Ask: How many groups of ten did you make?
    When children answer “2,” write the number.
  • Ask: After you made two groups of 10 beans, how many more beans do you have?
    After children say the number, write the second numeral next to the 2 and identify the new number. Have children repeat it after you and write it together. Continue by saying,
    Two groups of 10 and 4 more.
    The number is 24.


    When you are confident that children understand the concept of numbers greater than 10, play a guessing game.
  • Ask: I am thinking of a number greater than 12.
    It is less than 14. What is the number? Write it.
  • After children write the number, ask them to hold their papers in the air. Compare their answers and have them explain how they discovered the number. You may wish to have volunteers give similar clues to their classmates.

Wrap-Up and Assessment Hints
Provide many opportunities for children to count larger groups of objects. These concepts will take time for children to master, so it will be helpful to keep records of their progress.

Houghton Mifflin Math Grade K