Tarsia Maker builds printable triangle jigsaw puzzles that mark themselves. Each edge of a triangle carries either a question or its answer, and two pieces only sit together where a pair matches — so if the finished shape is right, the answers are right. You don't mark it. The puzzle does. Generate the pairs from a topic, pick a ready-made set, or type your own, then print the cut-outs and the answer key.
How to make a Tarsia puzzle
Typing your own pairs and printing is free and unlimited. Generating pairs with AI uses one token, and every account gets free tokens to spend.
A Tarsia is a jigsaw of matching pairs, cut into triangles, that a class rebuilds by matching questions to answers. Pieces join only where a pair is correct, so a completed shape is a correct shape.
It works for anything that comes in pairs — equations and answers, words and definitions, dates and events, a French word and its English one, a scientific term and what it means.
A couple of minutes, because the generate step does the part that used to take the evening. You type the topic — not just "fractions", but the corner of fractions you're actually teaching on Tuesday — and the pairs come back written.
If nine out of ten are right, you fix the tenth by hand in the preview. That's the whole job, rather than an hour building a table of pairs and then laying them out.
Use the modelling board before you hand any pieces out. It's a full-screen version of the puzzle where the triangles start scattered and slide into place one at a time, so you can build a few pairs with the class on the whiteboard and let them see how two edges lock together.
Most of the trouble with a Tarsia is children who haven't understood that the edges have to read correctly, and who start fitting triangles by shape instead. Two minutes on the board first heads it off.
It's just as useful at the end — because anyone who has run a Tarsia knows how it used to finish: half the class crowding round one table to check against a finished copy, or a puzzle that never quite came together going in the bin with nobody sure which pairs were wrong. An activity without a proper ending.
Now it has one. When the tables have had their go, bring everyone back to the whiteboard and reveal the answers pair by pair — each press brings a matching pair together, so every match gets seen, discussed and settled in front of the whole class while they check their own assembly against the board. That finale is why teachers across my school — we run from Early Years to eighteen — have picked it up in every phase.
From the classroom
The version of this that used to go wrong was the ready-made ones. I'd find a Tarsia online and it was either about roughly the right topic rather than mine, or it was pitched at a different class to the one in front of me. It half-worked — and half-working is worse than not bothering, because you've still spent the lesson on it.
What I do now is make more than one. The size control means a 16-piece puzzle goes to the table who'd finish a 9 in four minutes, and a 6-piece one goes to the children who need to get something right early to stay in the lesson. There's an age setting too — five bands from 5–7 up to 16–18 — so the wording comes back pitched at the class rather than at the topic's reading age.
Three versions of the same Tarsia takes a couple of minutes, because you're only changing two settings and pressing generate again. That's the bit that surprised me: not that it saves time on one puzzle, but that it's quick enough to stop making one puzzle for thirty children.
No. Tarsia Maker runs in the browser, so it works on a Mac, a Chromebook, a school PC or a tablet, with nothing to download and nothing for IT to approve. The original desktop Tarsia program is Windows-only and needs installing, which is why most teachers looking for one now are really looking for a way to make one without it.
Anything with a right answer and a fixed pair. Maths is the natural home — times tables, equivalent fractions, simplifying, unit conversions. But it's just as good for vocabulary and definitions, key terms in science, dates and events in history, and translations in French or Spanish.
It's a strong activity for children who need structure, because the task is closed. There's no blank page and no wrong way to start — you pick up a piece, you read it, you look for its partner.
And because the pieces have to be discussed, a Tarsia gets a table talking to each other about the content, which is hard to engineer any other way.
The PDF prints two pages: the puzzle pieces to cut out, and the assembled answer key for you. Card lasts longer than paper if you plan to use the same set again, and cutting one set per table rather than one per child is usually enough.
Written by a practising primary school teacher.
Making more puzzle activities? Try the Crossword Maker or the Word Search Maker — or turn the same matching pairs into a whole-class chain with Loop Cards.