Make it second nature.
Second Nature makes iPhone apps for things worth knowing by heart. Each one is built on memory research.
The first app teaches math facts.
Addition, subtraction, multiplication and division for kids about 8 to 11. One tap starts a 90-second round, and the app picks every card from the child's answers.
- A fact counts only when it comes in under 3 seconds.
- When misses pile up, new facts start with the answer shown.
- A grid shows which facts your child knows cold.

Every app teaches the same way.
The subject changes from app to app. The method stays, and it comes from research on how memory works.
Every card asks for the answer, never a choice among answers. Pulling an answer from memory is what makes it last.
The app picks each card so about 85% land. Too easy and nothing new is learned. Too hard and the learner quits.
A miss shows the answer, then asks for it again from memory. It comes back a few cards later.
Reviews come days, then weeks apart, so what was learned stays learned.
No ads, accounts, tracking or subscriptions.
Progress stays on the phone. One purchase unlocks an app for good, and Family Sharing covers the household.