Subjects
Choose questions individually, practise online, or create a worksheet with matching answers. Counts include generated variants, not only authored originals.
48 + 27 = 75. Regroup 15 ones as 1 ten and 5 ones; 4 + 2 + 1 = 7 tens.
48 + 27 = 75. Regroup 15 ones as 1 ten and 5 ones; 4 + 2 + 1 = 7 tens.
302 − 200 + 2 = 104. Subtracting 200 removes two too many, so add two back.
302 − 200 + 2 = 104. Subtracting 200 removes two too many, so add two back.
50 × 6 = 300
50 × 6 = 300
500
500
Multiplication can represent six equal groups of four, totaling 24; adding 6 and 4 gives 10.
Multiplication can represent six equal groups of four, totaling 24; adding 6 and 4 gives 10.
56
8 × 7 = 56
Start with the known part and count on to ten.
Grades K–1A group of ten can be exchanged for ten ones.
Grades 1–2For positive whole numbers, inspect the ones digit.
Grades 2–3A factor divides a whole number without a remainder.
Grades 4–7Use positive whole numbers. A common multiple is divisible by both.
Grades 4–7Distance is never negative.
Grades 6–8Rules, conditions and small examples in one printable reference.
Grades K–2Rules, conditions and small examples in one printable reference.
Grades 3–5Rules, conditions and small examples in one printable reference.
Grades 6–8A correction is stronger when it names the mistaken rule or place value.
Grades 2–5A correction is stronger when it names the mistaken rule or place value.
Grades 2–5Explain what a digit represents, not just which digit is largest.
Grades 1–3Explain what a digit represents, not just which digit is largest.
Grades 1–3Practise improper integrals, series, gradients and multiple integrals, with explicit conditions and worked examples.
Develop matrix, vector-space and projection reasoning before using least squares.
Connect initial conditions, linear differential equations and numerical approximation with error and conditioning.
Work with conditional probability, normalization, densities and expectation.
Build epsilon proofs and distinguish pointwise convergence, uniform convergence and compactness.
Study groups, vector-space quotients and proof techniques with carefully scoped definitions.
Study complex analysis, residues, Fourier series, PDE boundary conditions and convexity through focused lessons.
Learn descriptive statistics, probability, sampling and inference with worked reasoning.