Can he go to juvy for this? and wut exactly will happen?

ok so acouple of days before school ended this incident happened at recess (fifth grade by the way,my cl was like a mini jersey shore) so what happened was this kid lets say, BOB, and this other kid lets say, JOHN, were being stupid and taking the razors out of sharpeners . JOHN was playong with them first but threw them away because he knew it was wrong, but then BOB wantes to do it so he took the razors out of sharpeners and sharpened them at lunch. on our way out the clroom to recess BOB threw away the razors except for one of them (the ones that were thrown away supposedly had blood) . So then BOB and JOHN were playing this game where they pretend to kill eachother (interesting game right?) So BOB had the razor in his hand and was pretending to cut JOHN with it, but then ,of course ,he ended up actually cutting him , then JOHN said "if you cut yourself i wont tell on you" or BOB felt bad and cut himself (im not sure about that part :/) so then the teacher and our old teacher found out and JOHN said that he cut his arm on the fileing cabnet. Then the teachers knew JOHN was just lieing to not get BOB in troule because if BOB got in a lot of trouble he wouldn't be able to go to th banquet and bbq. So then JOHN admitted BOB cut him, then BOB went to the office and didnt come back , then after school (in after school care) my friend saw a cop car at the school and a police talking to BOB. and ever since then he didnt come back to school ,so basiclly that was BOBS last day of school. everyone said he went to juvy (the counselor wouldnt tell us :() so my question is , for what BOB did, could he dave gon to juvy?