Newton’s cradle with shapes

This toy combines the physics involved in Newton’s cradle with learning different types of shapes.  By pushing one or more of the shapes, a child can learn about momentum while also learning how to distinguish between and spell different types of shapes.  As the shapes move, so do the block of letters that spells their name.  This toy may be more appealing for children aged 5-7.  The strings would be made out of a sturdy but flexible material, such as thin metal, and the shapes and word blocks would be made out of heavier metal.  The outlying structure would also be made out of heavier metal to support the entire toy and make sure it is not prone to falling over.  The toy would be around 10 inches wide and 5 inches long.  The individual shapes would be about 2-4 cubic inches so as not to be choking hazards .  The only main safety concern would be twisting of the strings if the child is not using the toy properly.