She's studying volume.

I went to bed at 3:30 AM because Elysha went to bed early and didn't make me come to bed with her, so I stayed up all night writing and drinking A&W root beer.

Then Clara woke me up at 5:20 because she sleeps like her father, which is to say not much at all. She sat on my bedside, shook me awake and said, "Hey Daddy, we started a new math unit yesterday. Want to know what we're studying?"

I did not. I had been asleep for less than two hours at that point and had hoped to sleep until 6:30 AM. 

Not surprising, she told me anyway. 

It's 11:30 AM as I write this, and I'm a little tired, and it's all their fault.