This story shows a good part of what's wrong with our legal system. Some DA's are more interested in racking up a score of convictions than in serving justice. My guess is the DA doesn't actually intend to take this to trial and imprison these children, but by threatening that, he can get an easy plea bargain to a misdemeanor--Either that, or sitting in jail for a few days waiting to be tried on a felony is more punishment than an accurate charge could generate (in this case, it should have been handled in school)
We need to find a way to take away the worst of their weapons against decent people, without severely hampering how they deal with real criminals. I think the best way to do that would be to limit the ratio of original charge to plea bargain--If a prosecutor charges someone with rape or murder, they can't accept a plea of littering or disorderly conduct. I don't know what he exact ratio should be, but something like 50% of the penalty sounds reasonable. Probably also need something to prevent a points-scoring prosecutor from sending maxed-out charges to a jury, expecting them to drop most of them. Maybe a similar limit--Juries can only find one or two levels below what the prosecutor charges, otherwise either not guilty, or guilty without a sentence.
There should also be a real juvenile cutoff age, and anything that happens before cannot follow you forever. I'm not saying that if you're 17 and kill someone it's gone from your record when you are 18, but I do think stuff somewhere before around 14 or 15 should be expunged automatically after 5 or 10 years.