Choosing a tool or representation · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Picking the right tool

Mathematics · Mathematical Thinking · ages 6-7
Name ______________________   Date ____________

  1. You need to add 23 and 10. Which tool can help you count on?

    • Ruler
    • Number line
    • None, you can't use a tool

  2. Kim says a number line helps add two digit numbers. Is Kim right?

    Circle one:   True   False

  3. Which tool measures length?

    • scale
    • jug
    • clock
    • ruler

  4. Which tool would help you measure the length of a table?

    • Ruler
    • Number line
    • Hundred square

  5. A pencil is 9 cm. A pen is 6 cm longer. How long is the pen?

    Answer: ______________

  6. Why is a number line better than cubes for 47 plus 10?

    • ten jump is quick
    • cubes taste nice
    • lines are red
    • cubes are heavy

  7. Start at 51, jump back 10 on a hundred square. Where are you?

    Answer: ______________

  8. Why might you use a hundred square instead of counting in your head for 46 + 30?

    • You can see each ten as you count on, so you don't lose track
    • It's more fun to draw
    • It's the only way to add numbers

  9. Tom is measuring a pencil but picks a number line instead of a ruler. What went wrong?

    • He should have used a hundred square instead
    • He picked a tool for counting, not for measuring length
    • Nothing, a number line measures length just as well

  10. Ava says cubes are better than a line for 100 plus 100. Is Ava right?

    Circle one:   True   False

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Answer key

For grown-ups. Fold this page away before handing over the rest.

Picking the right tool W1-mt_zMEvtigoM3-s1

  1. Number line · A number line lets you hop from 23 up by 10 to find the answer.
  2. True · Jumps show adding tens and ones.
  3. ruler · Rulers measure length.
  4. Ruler · A ruler is made for measuring length, not for counting or adding.
  5. 15 · 9 plus 6 is 15 cm.
  6. ten jump is quick · One jump of ten beats counting cubes.
  7. 41 · 51 minus 10 is 41.
  8. You can see each ten as you count on, so you don't lose track · A hundred square shows tens in rows, so you can count on without losing your place.
  9. He picked a tool for counting, not for measuring length · A number line helps you count or add. Measuring length needs a ruler.
  10. False · Counting 100 cubes twice is slow, a line jump is quick.
Worksheet · LightMySky