The conspiracy theory that he "baited" his teachers is one thing, and that seems sketchy enough to me...after all we know that nobody believed for a moment that it was a bomb (or a "bomb trigger" as somebody on slashdot insisted); at worst they thought it was part of a failed plot to do a bomb hoax. A bomb hoax would be bad.
But seeing as there is no clear and present danger posed by something that could be mistaken for a hoax bomb, an immediate arrest was unwarranted. It shouldn't be possible to bait a school teacher into arresting you by having a disassembled alarm clock go off in your knapsack, especially when you identify it as a clock upon questioning.
It's substantially more wrong that a person can be arrested for this, than a student can play a prank.
That doesn't mean I think 15 million dollars should change hands. He did get arrested, but he was let go on the same day; he was unlawfully denied his civil right to speak with his father, but again, same day. He also got a short school suspension, which was also stupid but also doesn't mean a great deal of money should change hands. Bad arrests should be punished, commensurate to how bad it was.
I imagine 15 million dollars is just some lawyer throwing out a worst-case-scenario number and that literally nobody on Earth thinks 15 million dollars is on the table. My gut number is 10 thousand dollars. The law was abused and broken, and there has to be punitive measures taken for that; but mistakes will happen and the mistake was relatively low in scope.