Escher style Geometry Art from J. R. Masterman's 9th grade geometry class

Pokemon anime characters tessellate in this first-time tessellation by a 9th grade child

MEADOW by Tyler

Here's some symmetry art with a very different kind of theme.

This is a landscape theme. How can we tell where sand and grass and air begin or end? We can't. A "piece" of air can be any shape. A "piece" of sand or water or grass is the same: it has no definite recognizable size and shape. This is why typically a landscape isn't the theme of a tessellation. Many tessellation artists say "we should be able to recognize the topic by its outline". Can we do that with this outline? No, not really.

However, it's some very good looking art, isn't it.