3rd Grade Review | Math Mystery Worksheets | Back to School | Multiplication Fractions

A whole year of 3rd grade math, one topic per detective case — students solve each problem, write the answer in the box beside it, match it to a suspect, and cross suspects off until one is left standing. This no-prep, printable, self-checking Math Mystery is built for the first weeks back, and works just as well for spiral review, math centers, morning work, homework, early finishers, substitute/relief days and test prep. One page per topic means you can run one case a day or use the whole pack as a diagnostic.

Quick Details

Skill: Whole-year 3rd grade review, one topic per case · Grades: 3–4 · Format: 10 mysteries + full answer keys (printable PDF) · Theme: Back to school detective

The 10 Mysteries

The Canteen Count — Every lunch order has been multiplied by the wrong number and nobody can pay.

The Shared Snacks — The snack boxes were shared out overnight, so students work out each missing number in a division.

The Sports Day Ledger — Someone rewrote the ledger and the totals no longer add up; the graph holds the clues.

The Rounded-Up Roll — Every number on the school roll has been rounded off and the real ones have vanished.

The Library Tally — The book tally has been changed on every shelf label in the room.

The Minute Hand Heist — Every clock has been moved by a few minutes, so students write the digital time on each.

The Garden Plot Puzzle — The bed markers have been pulled out and swapped, and students find the area or the perimeter of each.

The Shape Shed Scandal — The shape boards were tipped out and jumbled, so students add the sides and the right angles.

The Painted Panels — The mural panels were cut into equal shares and part of each painted over.

The Pantry Share-Out — Someone took a fraction of everything on the shelves, and students work out how much went.

Why Teachers Love It

Zero prep — print and teach. The built-in answer keys make every case self-checking, so students get instant feedback and stay motivated. One topic per page means the pack works as a back-to-school diagnostic, a fortnight of morning work, or ten separate centers — and the detective hook pulls in reluctant and struggling learners who would stall on a plain review sheet.

Skills Covered

Multiplication facts, division and missing numbers, reading a graph, rounding, telling time to the minute, area and perimeter, the sides and right angles of 2D shapes, equal shares, and fractions of a set — plus logical reasoning and deductive elimination as students rule suspects out clue by clue.

What's Included

Printable one-page mystery worksheets, one math topic on each, suspect line-ups, complete answer keys with the villain marked, and student instructions — all in one PDF.

Best Used For

Back to school review, beginning-of-year diagnostics, spiral review, math centers, morning work, homework, early finishers, substitute/relief days, and test prep for grades 3–4.

More From This Line

Browse every Math Mystery pack, or pick up the grade either side with 2nd Grade Review and 4th Grade Review.