One snip! Watch the teacher cut a paper square corner to corner. One square went into the scissors. What two shapes came out?
Three builds on the board. Look carefully: where do the small shapes meet? That meeting place is the join line (the line where two small shapes touch). Trace each join line with your eyes. The small shapes are still there inside the big one.
On the last build, count the small triangles. Then find every join line.
One friend builds on the board. Everyone else watches for gaps and overlaps. Every edge must meet another edge.
Build the shape from smaller blocks
In your maths copy, draw a square. Then draw the one line that cuts it into two triangles, corner to corner. You may trace a square from your Shapes to cut out sheet if you need a steady start.
Four builds at the board, one at a time. After each one, point to where the small shapes are still hiding.
Build the bigger shape
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