Today is rung 2 of 7 on this topic
Equivalent fractions
Can do: Recognises that 1/2 = 2/4 = 4/8, and can generate an equivalent fraction.
Why it matters
Equivalence is what makes adding fractions possible in Grade 4 and 5. Without it, every fraction operation is arbitrary.
What it looks like when it's wobbly
Sees 2/4 and 1/2 as different amounts, and applies the multiply-top-and-bottom rule with no idea why it's allowed.
โฑ๏ธ Two-minute check
"Is 2/4 the same as 1/2? Prove it. Now give me a fraction equal to 1/3."
Solid looks like: A proof by picture or strip, and 2/6 or 3/9.
The full activity for this topic ยท 15 minutes
Same Amount, Different Name
- 1Lay 2/4 directly on top of 1/2 and check they match exactly.
- 2Ask what happened to the numbers: both doubled. Draw the arrows.
- 3Fold a strip again to turn quarters into eighths, and watch the numbers double again.
- 4Try it with thirds and sixths so it isn't only about doubling.
- 5Use a real one: half a cup versus two quarter-cups in actual cooking.
If it's too hard
Halves, quarters and eighths only.
If it's too easy
Simplify the other way โ reduce 6/8 to 3/4 and explain the division.
Say this
"Same amount, different name. What did we do to the top? What did we do to the bottom?"
