Math Lab

1. Pick a problem from the list down the left. It is grouped by topic, from Numbers to Vectors & motion; tap a topic to open it, and the others fold away. Each problem says which grades it suits. Type in Find a problem to search, or press Grades 3–5, Grades 6–8 or High school to see only those. On a phone the list folds into a bar above the notebook; tap it to open the list.
2. Set the numbers with the − and + buttons, the slider, or by typing. The question on the right page changes with them.
3. Type the answer to the first step and press Check. The next step opens only when this one is found. Where an answer can be below zero there is a ± key, because a phone keypad has no minus.
4. When every step is done the page says Solved, and how many steps were your child’s own.
5. Back a step undoes the last step found, and Start over clears all the working but keeps the numbers. There is no need to reload the page.

A wrong try says Not quite. Try again. and offers A hint, then Another hint. Neither hint gives the number away. After three tries your child may press Show me this step; that step is written in and marked as shown.

Under the drawing, Show all steps fills in the whole working at once, every step marked as shown. It is there for checking, or for a child who is stuck; changing a number puts the problem back to the start. On dividing on paper, the empty boxes show the shape of the whole working from the start, before any number is in them.

Eighty-two, all math, in thirteen topics. Grades 3 to 5 have adding, taking away, multiplying and dividing on paper, area and perimeter, equal fractions and fractions of a number. Grades 6 to 8 have numbers below zero, powers, percents, ratios, equations, the area of every flat shape, angles, a cube and a box, the mean and chances. High school has every algebra identity from (a + b)² to a³ + b³ + c³ − 3abc, everything about circles (arcs, slices, chords, tangents, angles, a circle on a grid), cones, spheres and pyramids, laws of powers and logarithms, distance, midpoint and the line through two points, trigonometry, and two first steps in calculus.

Formula sheet, beside the Math Lab title, lists every formula on one page, grouped by topic, with a search box. Work one out under a formula opens that problem, ready for your own numbers. The sheet prints cleanly.

It does not read a question your child types in their own words, and it does not take a photo of homework. Every number and every step is worked out on your device by Cogito itself, so nothing your child does here is sent anywhere. It is free, with no sign-in.