Khan Academy
Khan Academy: Rotate 2 D Shapes in 3 D
Practice your 3D visualization skills by rotating 2D shapes. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Better Lesson
Better Lesson: Making New Shapes With Shapes
My first graders have been studying the defining attributes of 2D shapes. They are going to love using toothpicks and marshmallows to present their knowledge of 2D and create 3D shapes.
National Council of Teachers of Mathematics
Nctm: Illuminations: Volume of a Cube
"The volume of a cube can be developed by considering unit cubes, a single row (longs) of unit cubes or a single layer (flats) of cubes using this applet." This easy software makes it possible to easily construct a cube and take it...