A ready-to-run lesson on deductive reasoning, with free printable worksheets and answer keys.
Logic grid puzzles are one of the cheapest ways to get students reasoning out loud. There is one rule to learn, every clue is short, and every puzzle has exactly one answer, so students can tell when they've got it right without waiting for you. Best of all, the answer alone isn't the point. The interesting part is the chain of “because” that gets you there, and that's exactly what you want students practicing.
Logic Dogs puzzles come in four levels. The step counts below are the median number of deductions in our step-by-step walkthroughs across each level, so they give a fair idea of how long a chain of reasoning each one needs.
| Level | Typical steps | Good for |
|---|---|---|
| 4x4 Easy | 12 | A first lesson at any age. Simple clues and several squares already filled in. |
| 4x4 Hard | 16 | A second lesson, or students who finished 4x4 Easy quickly. |
| 6x6 Easy | 42 | Older students who are comfortable with the scratch grid. Plan for a full lesson. |
| 6x6 Hard | 55 | Extension work and puzzle clubs. Some puzzles need a “what if” test. |
As a rough guide, confident readers in upper elementary school can usually handle 4x4 Easy with some modeling first, and 6x6 suits middle school and up. Reading level matters more than age: if the clues are hard to read, the logic never gets a chance.
Print 4x4 Easy, Pack 1. The puzzles are ordered easiest first, so Puzzle 1 is your demonstration and Puzzles 2 and 3 are for students. Print the answer key separately, for yourself.
Draw the answer grid on the board: locations across the top, categories down the side. Explain the only rule: every location gets exactly one item from each category. Ask what follows if you know the akita is at the Park. Students should come up with both halves: no other dog is at the Park, and the akita isn't anywhere else.
Solve the first few clues of Puzzle 1 in front of the class, saying every thought out loud, including the ones that go nowhere. Show the two marks on the scratch grid: ✗ for “can't be here” and ● for “must be here”. Make a point of choosing which clue to use next: clues that place an item outright come first, and clues about two items get more useful as the grid fills up.
Students work in pairs on Puzzle 2, then Puzzle 3. One rule for pairs: no mark goes on the grid unless both partners can name the clue that justifies it. Walk around and ask “which clue tells you that?” more than you give hints. If a pair is truly stuck, point them to a location instead of a clue: “What could go at the Beach?” That nudges them toward scanning a column, which is the most underused move.
Pick two or three pairs to explain a single step each, not a whole solution. Good questions to finish on:
These come up in nearly every class, so it's worth naming them before students start.
For students who need support: read the clues aloud together first; cut the clue list into strips and have students sort them into “tells us something right now” and “useful later”; or fill in one extra square of the answer grid before handing it out.
For early finishers: move up a level, or try a harder pack. A good challenge is to hunt for a clue that could be deleted without the puzzle losing its single answer, then prove it by solving the puzzle again without that clue. Most clues are essential, but not all: in the 4x4 packs, about one clue in 25 turns out to be extra. Finding one, and explaining why the puzzle still works without it, is real proof-writing.
For a puzzle club: the hardest daily puzzles page lists the toughest puzzles we've published, and every archive page includes a full step-by-step walkthrough students can compare against their own reasoning.
Every puzzle in the printable packs is also in the Logic Dogs game, which runs in any web browser. Students don't need an account to play. The Check button tells them how many squares are wrong or missing without saying which ones, and hints start gentle (pointing to a category of clues to look at) before getting specific, so the game nudges rather than giving answers away. There are four new daily puzzles each day, and the how to play page explains the controls.
Everything here is free to print and copy for your class. If you use Logic Dogs with students, we'd love to hear how it went and what would make it more useful. Get in touch.