FractionExplorer

Build improper fractions to understand them — not just compute them.

Click each pizza slice to place your pieces. Watch wholes form — then see the fraction revealed as a number. This is how your brain builds lasting understanding.

Your challenge

You ordered 7 pizza slices. Each pizza has 4 slices. How many whole pizzas do you have?

Click each slice to place your pieces into pizzas.

Slices placed0 / 7

Pizza 1

Pizza 2

Try another fraction:

Halves
Thirds
Quarters
Fifths
Sixths
Why this works

Area model beats number lines

Tian et al. (2021) tested both formats with P4 and P5 students. Area model training produced significant gains on improper fractions. Number line training produced no improvement at all.

Story first, symbol second

A preregistered RCT by Viegut and Matthews (2023) found that analogy-based instruction produces gains that last at one-week follow-up. Partition-drag alone fades. The pizza story here is the mechanism.

Concrete to abstract (CPA)

Without bridging visuals to symbols, learning stays isolated. Willingham (2017) showed students often never connect the two without explicit instruction. This tool follows Singapore's own CPA framework — you build first, then see the number.