When a math skill feels impossible, the problem is often not that skill itself. It is a skill underneath it that never quite settled: a math gap. This pyramid shows every skill your problem is built on, from kindergarten up, and tells you exactly where to start.
It is free, it takes a few minutes, and it works whether you are a student falling behind in math, an adult re-learning math you forgot, or a parent or teacher trying to find the missing skills behind a struggle.
Pick the skill you are stuck on. The pyramid shows the prerequisite skills right underneath it, and opens deeper rows only where you have a gap.
Or pick one:
Be honest with "I've got it". Press it only when you can do that skill on your own, quickly and without mistakes. If you are not sure, press "Try one" first. A skill you only half know is often the hidden reason the skill above it feels hard.
If you are falling behind in math class, more practice on this week's topic often does not help, because the trouble started earlier. Pick the topic from class, and the pyramid walks you down to the skill you missed. Fill that gap first, and the topic from class gets easier.
If you forgot most of your school math and do not know where to start, you do not have to begin again from 1 + 1. Pick the skill you need now, for a course, an exam or a job, and press "I've got it" on everything you still know. The pyramid skips those skills and sends you straight to what you need to review.
Many students struggle with algebra because of skills from earlier grades, such as fractions, negative numbers and the meaning of the equal sign. Pick an Algebra 1 skill, such as two-step equations, to check whether you have the prerequisite skills before algebra starts.
When a child is struggling with math, the pyramid helps you find the math gaps underneath the struggle. Sit down together, answer the rows, and you get a short list of skills to fill, in the right order, with a lesson for most of them. For more ideas on studying math well, see How to Learn Math.
Behind the pyramid is a map of 316 skills taught in school math, from counting in kindergarten to calculus. It covers the US Common Core standards from kindergarten to grade 12, grouped into the usual courses (Algebra 1, Geometry, Algebra 2, Precalculus), plus the topics of AP Statistics and AP Calculus AB and BC. Each skill is linked to the skills it directly needs.
Every skill also has a short note on why it can feel hard. These notes come from research on how students learn math, and from my own experience as a certified teacher who has taught math both in the classroom and online. Research shows which mistakes are common. Teaching shows me how they look in real students: the same few traps come up again and again, whatever the grade. Most struggles go back to these:
Every link between two skills comes with a short note that shows exactly where the lower skill is used inside the higher one. For example, adding 12 + 13 means rewriting both fractions as sixths, and that rewriting is equivalent fractions. When research shows that one skill is the most common cause of trouble, the pyramid marks it "Most common gap", so you can check it first.
When you finish, the pyramid shows your starting skill and the chain of links from it back up to your goal, so you can see why each step matters. Your answers are saved in this browser.
Practicing the same hard skill again and again without checking what is underneath. If a skill does not get easier with practice, step down the pyramid. The real math gap is often one or two rows below, and filling it is what makes the skill above it click.
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