SE 3.05Constructive Triangles: Rectangular Box 1
The child joins colored triangles along their black guide lines to build squares, rectangles, and other shapes.
Age 4–5½Work 5 of 7 in Visual — Form
Presentation
- 1
Take out the triangles and sort them by color and shape on the table.
- 2
Pick up two matching triangles and point to the black line on each.
- 3
Slide the two triangles together so the black lines meet, forming a new shape.
- 4
Name the new shape if the child knows it (for example, "square").
- 5
Continue with each set of triangles until every shape is built.
- 6
Look at the finished shapes together and return the triangles to the box.
Extensions, easiest to hardest
- Place the triangles on the Geometric Cabinet insets of the same shape to compare.
- Build new shapes by joining triangles along different edges.
- Trace the finished shapes on paper and color them.
Control of error
The black lines: when triangles are joined correctly, the black lines meet exactly along the join.
Ready to move on when the child…
- Joins all pairs using the black lines
- Names the shapes created
- Makes new shapes independently