Just following the standard advice: don't talk to police without a lawyer present. They're not there to help you, they're asking questions to find an answer to hang you on.
That standard advice is good advice. For the innocent. And the guilty.
Thing is - there are no innocent people with a history (even a 14 year old kid) of making bomb like devices in school, so if - as we know from previous reports - this kid was known to cops already as a provocateur; then yeah.
Put the little creep in cuffs and take him downtown.