What is Long, What is Round?

2D shapes are flat — they have length and width but no thickness. Types: Circle (no corners, no sides), Square (4 equal sides, 4 corners), Rectangle (2 long + 2 short sides, 4 corners), Triangle (3 sides, 3 corners). Look for shapes around you: clock=circle, window=rectangle, pizza slice=triangle, dice face=square.

3D shapes have length, width and height — they are solid. Types: Sphere (ball shape — no flat face), Cube (6 equal square faces — dice), Cuboid (6 rectangular faces — brick), Cylinder (2 circular faces, 1 curved surface — tin can), Cone (1 circular face, 1 curved surface — ice cream cone). Roll test: sphere and cylinder roll; cube and cuboid slide.

Faces: the flat surfaces of a 3D shape. Edges: where two faces meet. Corners/Vertices: where three or more edges meet. Cube has 6 faces, 12 edges, 8 corners. Cuboid has 6 faces, 12 edges, 8 corners. Sphere has 0 faces, 0 edges, 0 corners — it's all curved! Count the faces, edges, corners of objects around you.

Buildings use cuboids (walls), cylinders (columns), pyramids (rooftops). Kitchen: cylindrical pots, spherical fruits, cuboid bread. Sports: football (sphere), cricket bat (cuboid), coin (cylinder). Nature: eggs (oval), tree trunk (cylinder), mountains (cone). Engineering uses shapes because they are strong, stable or efficient.