Same amount. New pieces!

SparkClass

Slice every piece, change the fraction’s name, and keep the colored share exactly equal.

CCSS 3.NF.A.3a–b
Live Fraction Bars
Equal Amount
Two equal-length fraction bars and a number line The top bar shows one half. The bottom bar shows two fourths. Both have the same colored width and mark the same point on the number line.
01

More pieces, smaller pieces—the same amount. Each original piece is sliced into 2.

Original1/2
=
New Name2/4
Same Colored Width

Make the equality visible

Use the bars before the notation. Students should see why the amount does not change before naming the multiplication rule.

1

Start with a fair share

Choose a fraction and ask what the colored part means. Keep both bars the same total length so one whole is clearly the same size.

2

Slice without adding color

Play the slicing animation. Ask: What happens to the number of pieces, the size of each piece, and the colored width?

3

Connect the model to m/m

Point to the shared location on the number line, then connect each new piece count to multiplying numerator and denominator by the same m.

CCSS alignment: 3.NF.A.3a–b — understand and generate simple equivalent fractions, and explain equivalence with a visual fraction model. This lab uses proper fractions from 0 to 1.