A conversation last Thursday...
Student: How big is your baby now?
Me: About 3 centimeters.
Student: Awwww!!! That's so cute!
Student: ...Wait, if the baby's only 3 centimeters, then why do you have a belly?
I smile and try to think of the best way to answer the question.
Me: Well, you don't gain all the weight at the end of the pregnancy when the baby is big. It's spread all throughout the pregnancy.
Student: Oh. Okay.
DH said that I should have instead told my student that I was eating her lunch behind her back :)