Math Investigations

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Chapter 2

Part 1: Home and School Investigation

Send the Letter to Family (PDF file) home with each child. Once all of the children have brought in a puppet made from a brown paper bag, put the children in pairs and ask each child to have his or her puppet tell the other puppet what addition fact it shows.

You might want to continue using these puppets perform short plays. Try to incorporate addition facts into the plays.

Part 2: Be an Investigator

A good time to do this investigation is after Lesson 5 on making 10 to add.

Materials

  • one Investigator Worksheet (PDF file) for each pair
  • colored counters (2 colors)
  • bag containing slips of paper each with a number from 10 to 18 (each pair draws one number)

Introducing the Investigation

Ask children how many different ways they can think of to make the number 8 by adding two numbers. Write down the addition expressions they suggest. The list is:

0 + 8 (and 8 + 0)
1 + 7 (and 7 +1)
2 + 6 (and 6 + 2)
3 + 5 (and 5 + 3)
4 + 4

Show each addition expression with two-color counters. Each color should represent one part. Provide students with the Investigator Worksheet (PDF file).

Doing the Investigation

Tell the children that they are going to draw a number out of a bag. They are going to see how many different ways they can find to make that number by adding two numbers less than ten. They may choose to use counters. Have them list all the ways they found.

You might want to display the children's work in the classroom.


Houghton Mifflin Math Grade 2