Why this exists

If you ask someone who says they are bad at math when it started, most of them can tell you, and it is usually a specific thing in a specific year. They were keeping up, and then one day they weren't, and the way the room worked made asking feel more expensive than staying quiet. So they stayed quiet, and the thing they missed became the thing everything else was built on, and every year it got a little more embarrassing to bring up.

This is not a small group of people, and the numbers are worse than most people assume.

• 41% of American eighth graders scored below Basic in math on the 2024 national assessment, which is the largest share in the history of the test. Below Basic means they cannot reliably add two fractions or solve a one-step equation.
• 34% of American adults, somewhere around 72 million people, are at the lowest numeracy level or below, and that share went up between 2017 and 2023 rather than down.
• Students who fail Algebra 1 graduate on time about half the time, and most of them were already behind on the day they walked into the class. Algebra 1 is just where an older gap finally gets a grade attached to it.

The tools that could help tend to make the quiet moment worse rather than better. One charges by the month and docks your score when you miss. One needs a code from a teacher before you can see anything. One puts forty minutes of video between you and the practice, and one turns the whole thing into a game with hearts you can lose. All of them need an account, which means all of them keep a record of what you didn't know.

So we built the opposite

You get a fresh problem and you try it, and the moment you submit you find out whether you had it. If you are stuck you ask for a hint, and the hint is exact because it was written for that particular problem, and nobody sees that you asked. Nothing ever goes down and nothing you do here leaves your browser. Then you get another problem, and that is really the whole thing.

Sources: NAEP 2024 grade 8 mathematics, NCES. PIAAC 2023, Institute of Education Sciences. High School Longitudinal Study of 2009, NCES.