Math Investigations

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Chapter 21

Part 1: Home and School Investigation

Send the Letter to Family (PDF file) home with each child. Once all the children have brought in ads from the newspaper, put the children in pairs. Have them find the total cost for both of the items in their ads. If you want children to do this more than once, just have the children change partners.

Part 2: Be an Investigator

A good time to do this investigation is after Lesson 4 on adding money.


Introducing the Investigation

Put the children in groups of two and show them the worksheet. Tell them that you would like them to figure out how many different ways they could choose two toys that are on the worksheet. Then ask them to find the total cost of each combination.

Doing the Investigation

This investigation provides an excellent opportunity for students to use the problem-solving strategy of making an organized list.

Observe children as they are writing down the addition problems and adding. Make sure they are lining up the digits correctly. You might want to provide grids to help children line up the digits, as suggested in the Teacher's Guide on page 612.

table with heads called dollars and cents, and $4.39 + $1.25=$5.64. equation aligns on the decimal point.


car, teddy bear$8.25
car, kite$6.75
car, ball$5.25
teddy bear, kite$8.00
teddy bear, ball$6.50
kite, ball$5.00

Houghton Mifflin Math Grade 2