I’ve been asked to re-post this link to a lengthy written and video presentation about how to use the LEA 3-D puzzle.
If you would like to learn more about this puzzle, please check out the link below (it takes you to 7 videos and an extensive write up.

We use that puzzle with all of our little kiddos who have severe vision impairments. It’s a toy! They love it! But, oh, does it help that low vision doctor when they finally come for their visit!
I have used the LEA 3-D Puzzle for years with the Birth to Three children I work with through the outreach program. Perceptual information is grained in preparation for the the LEA Symbol testing. Kathleen