If only we really were... Blowing up stuff is one of the best introductions to science a kid can get!
If a kid today were to do now what I did as a kid, they'd have a criminal record a mile long, destined to be nothing more than a drain on society since they'd be permanently branded and unemployable in most places. That's not a good way to build up your future economy and industry, not to mention international competitiveness!
Punishing a child by permanently destroying their hopes and dreams shows some badly misplaced priorities.
People argue as though there is some sort of dichotomy; that either she ought to be prosecuted or exonerated entirely. Both are absurd. What she did was dangerous and clearly impermissible, and the school should take action. I don't think that this warranted legal action, but I've learned not to assert things about the law, which is a complex and unintuitive beast. There is a possibility of reasonable middle ground in which we don't permanently impede someone's ability to live their life while also deterring them from detonating explosives in school.