Think • Explain • Check
A small question.
A useful conversation.
Find every triangle in a clear diagram, then explain a list that checks your answer. Download a square image or a two-page printable with a separate adult answer page.
For adults preparing activities with learners who can recognize triangles and follow a labelled diagram. Free, no signup; downloads are made in your browser.
One carefully selected question, with a complete answer list. More topics will be added after research and review.
PNG: 1080 × 1080, question only. PDF: participant page + adult answer page. Print at actual size.
Hint
Answer and a related question
Use it as a 10-minute discussion
- Read the counting rules and allow quiet thinking time.
- Ask participants to trace a triangle and explain their first step.
- Offer the hint before showing the answer.
- Check the complete list, then discuss the extra-base question.
The triangle-counting discussion guide includes timing, support options and a printable diagram with a recording sheet.
What counts?
Only the drawn straight lines form sides. Overlapping triangles count. Different positions count separately even if shapes are the same size. Labels A, B and C name rays from the top; 1 and 2 name horizontal bases. Labels are outside the shape.
Why this topic?
Triangle-counting posts have attracted guesses and explanations on X. That helped us choose this topic; it does not predict how our own card will perform. We drew a simpler original diagram and added explicit rules and a complete list. See the historical discussion and a recent example. Our card is a teaching adaptation, not a copy of either post.
Prepare for your participants
Trace with a finger, read labels aloud or work with a partner. The card offers counting and explanation practice; it does not measure intelligence or prove improved reasoning ability. Preview both pages before printing.
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