Our library has a dress up area. My 3 year old son was asked what he wanted to dress up as... He said he was trying to decide between a suspension bridge and an embryo. The other parents were horrified and kind of shuffled their kids off to other areas. He was being genuine and we figured out ways to use the costumes to do both and had a grand time.

An out of town museum had a display on amniotes that fascinated him, so he thinks embryos are interesting. To my son, embryo => person is no more embarrassing than tadpole => frog or caterpillar => moth. This is not necessarily consistent with our current community, which also largely rejects any thought related to evolution.

He is also excited to discover his food looks like various countries, US states, or shapes. Look Mom, it's Australia!... Look, Idaho!... Look, a hexagon! It is fun, but sometimes lunch takes a really long time.