Grading math homework: partial credit, tolerances, and ¾ = 0.75

Math homework is deceptively slow to grade. The answers are short, but checking them is not: a fraction that equals the decimal on your key, a right answer with the units left off, a worked problem that went wrong in step three but right everywhere else. Bubble-sheet tools cannot touch it, and marking by hand is a long night of small judgements. This is where photo grading does the most work.

It reads the answer as a value, not a string

Your key says 0.75; the student wrote ¾. A tool that compares text marks it wrong; SuperGrader knows they are the same value. Fractions, decimals, scientific notation and simple expressions are all evaluated before comparison, so 3/4, 0.75 and 6/8 land together, and 2π matches 6.283…. You grade the maths, not the formatting.

Tolerances and ranges, the way you actually mark

Applied problems rarely have one exact right number. Put a tolerance on the key — 9.8 ± 0.2 — and anything inside the range is correct. Units are checked alongside the value, so 9.8 m/s² and 9.8 m/s are not confused, while m/s² and m/s^2 are treated as the same unit. The key carries your rules; the grading applies them the same way every time.

Partial credit on a worked problem

A student who sets the problem up correctly and slips on the arithmetic has not earned a zero — and shaded-circle grading can only give one. Because SuperGrader reads what the student actually wrote, a worked problem can earn partial marks against your key, and anything the reader is unsure of is flagged for you rather than scored wrong.

Still your key, still your call

None of this is an AI deciding what is close enough. You photograph the answer key, confirm it, and the deterministic engine applies it — the same paper scoring the same way every time, every mark traceable to the question. You spend your evening on the few problems that need a teacher’s eye, not on checking thirty fractions by hand.