What shapes tessellate?

Last week Dean, Walter and I were out on the playset swinging. As I was pushing them, Dean (3 y.o.--ok 4 at the end of the month) asks, "Mom, what shapes tessellate?"  I was pulling out of the back corners of my brain that tessellation was a repeating pattern, so I said, "I think all of them do buddy."  To which he replied, "No mom. Shapes that tessellate can't have any overlaps or gaps when you put them together."  HA! When I asked where he learned that he said, "Cyberchase." (a PBS show/games online).  At least he's learning things when he plays those games...there are some redeeming qualities to certain gaming.


So, I decided to print out some shape pattern pages from this site and let them color them. When Dean got out the shapes I made he says to himself, "Tessellation.  When you use a single shape in a repeated pattern without any overlaps or gaps." He is a little dictionary! I cut them out and Dean really enjoyed playing with them as long as they cooperated (didn't leave any gaps or overlaps--a little tricky with paper). I wish I had the little pattern blocks since it would have been easier to work with, but this was cheap and accessible.  While we were doing it he kept saying, "MOM! Hexagons really DO tessellate!!!!" After we finished and we were playing in his room, he asks, "Mom, do rhombuses tessellate?"  My answer? "Let's go see!" (ie., I'm not totally sure what a rhombus is, so lets go look at pics on the internet.  For any who may have forgotten like I had, a rhombus is just a diamond.)