always

It is known for a fact that accidental magic often happens when a (young) witch or a wizard is really angry, really scared, or really confused. Not to mention in a state of a high stress which can involve all of those emotions.
And then something magical happens, usually something horrible, to the person or thing that is causing the emotions on the witch/wizard.

The books make a big deal about accidental magic, and how young children have little to no control over their magic and thus do a lot of accidental magic.
But obviously they're doing something about it, as the magical society is still...

Ways to piss off Hermonie!
1. Say that the smarter you are, the quicker you die.

2. Tie her to a chair and tell her she can't get up until she finds the last number in pi. (3.14...................)

3.Lock her in a room that has a gun with one bullet and repetitively plays Hillary Duff soundtracks

4. Force her to read a German dictionary and write a 10 page book report on it.

5. Throw water balloons at her and tell her you wanted to know if she would melt.

6. Stick her in the Jar with Rita Skeeter.

7. Force her to sing, "The Real Slim Shady."

8. Follow her to the library and everytime she opens a book,...