I was teaching 6th grade Science class and I complained to the class that their absentee rate was too high. A student raised her hand and said "Well, our teacher makes us sick.".
Sometime later, I was talking to a plant in the classroom trying to make the point that we exhale CO2 which is what plants need to grow. I said "what am I trying to do by blowing my breath on the plant?" A student replied "kill it". I asked the class class if I had bad breath, a student replied yes, but it's OK "all teachers do".

There is nothing faster than a toddler that was just asked "What's in you mouth?"

Kids do say the funniest things and though provocking lol