Science at the dinner table

Last night we were having dinner and we each had ice in our drink. Halfway through the meal Venus looked into her cup and said "My ice is gone". Not wanting to miss an opportunity for a science lesson we asked her where she thought it had gone. The conversation went like this:

Venus: "It turned into water." 

Supernerd: "What would you do if you wanted it to turn back into ice?"

Venus: "Put it in the fridge."

Supernerd: "Would it turn to ice there?

Venus: "No, it would just be really cold. It would have to go in the freezer."

Supernerd: "Why would it have to go in the freezer?

Venus: "Because it's all freezy and cold in there."

Supernerd: "That's right. Because the freezer is colder than the fridge."

Mars: "I know where else you could put it... in your anus."

In the moment between moments I was thinking just how unhappy I was that some obnoxious kid at school had taught him to be so rude, but the next thing he said was:

"Because uranus is a long way from the sun and it's really cold there."

So now I'm trying to teach him to pronounce it uRANus, which is the way I was taught as a child. It's not going well, but it's probably easier than trying to explain to him why I was choking on my dinner.