Wemazi

Which & Why

Apps that help students learn, and remember.

Which & Why follows the AP course topic by topic. When you're stuck, you solve it together, step by step, and a review a week later checks what stuck.

Why it works

We forget fast. Reviews slow it down.

Most of a new lesson is forgotten within a day. Every time you go back over it, you forget it more slowly. That's why Which & Why brings each topic back a week later.

What's left of a lesson

With reviews Without A review
This picture shows the general pattern, not data from one study. The reviews happen 1, 3, 7 and 14 days after the lesson.
For students and parents The science of learning Why we forget, why spacing works, how rewards help and the three stages of learning. Five short animations, about six minutes.

Every topic has three stages.

Learning

You've answered a question in the topic. Help is welcome.

Without help

Every skill right on two different questions, on your first try, on your own.

Remembered

A week later, five right in a row that cover every skill.

Why learning happens in three stages

Free to start.

The first two units of each course are free, with every feature. One purchase unlocks the full course. No account, no ads and no subscription.