Broken Calculator
Grade 3 Mathematics
Routine - Broken Calculator
Standards: 3.OA.4, 3.OA.5, 3.OA.6, 4.OA.1, 4.NBT.5, 4.NBT.6, 5.NBT.6, Mathematical Practice #5
In this routine, students are challenged to solve multiplication and division problems on the calculator without the use of those particular keys on the calculator. For example, in multiplication, students can be given the problem 36 x 4, and challenged to find the product on the calculator without the use of the X key, therefore helping students relate multiplication to repeated addition. In the division example, students are given a division problem such as 91÷7 and challenged to find two ways to solve it using the calculator (but not using the ÷ key). This activity can help students see the connection between division and multiplication as inverse operations and/or division to repeated subtraction.
| Grade 3 examples: | Grade 4 examples: | Grade 5 Examples: |
| 5 X 3 | 17 X 6 | 257 X 8 |
| 6 X 7 | 58 X 5 | 2,456 X 6 |
| 4 X 10 | 123 X 8 | 8, 290 x 4 |
Routine - Broken Calculator - Multiplication Links to an external site. on Vimeo Links to an external site..
| Grade 3 examples: | Grade 4 examples: | Grade 5 examples: |
| 45 ÷ 9 | 36 ÷ 4 | 315 ÷ 7 |
| 24 ÷ 6 | 78 ÷ 6 | 216 ÷ 9 |
| 80 ÷ 10 | 225 ÷ 5 | 2, 870 ÷ 5 |
Routine - Broken Calculator - Division Links to an external site. on Vimeo Links to an external site..