Math Investigations

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Chapter 22

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 difference in the cost of the items in their ads. If you want children to do this more than once, have the children change partners.

Part 2: Be an Investigator

A good time to do this investigation is after Lesson 5 on subtracting money.

Materials

Introducing the Investigation

Put the children in groups of two and show them the worksheet. Ask them to pick out a toy each of them would like to buy and circle it. Tell them to pretend that each child has $2.38 and needs to figure out how much more money is needed to buy the toy.

Doing the Investigation

Observe the children as they are writing down the subtraction problem and subtracting. Make sure that they are lining up the digits correctly. You might want to provide grids to help the children line up the digits, as suggested in the Teacher's Guide on page 634.

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

Answers:

  • toy airplane: need $6.14 more
  • doll: need $5.16
  • toy robot: need $7.08
  • toy boat: need $4.53

Houghton Mifflin Math Grade 2