You could also use an item like this to check right angles, acute angles and obtuse angles in your shapes, too. Start at the number 0 on your ruler, not at the end of it. Make a dot at the number ...

Suitable for: Teaching KS1 Maths, focusing on geometry including 2D and 3D shapes, position and movement, angles, coordinates and maps. Titch and Ted - Introduction to Geometry (pt 1/6 ...