.Most people on this thread are not concerned, as you are, with the size of the sissors or that the girl had them in her backpack (you chose to use the word hidden as though everything in one's backpack is hidden)
NO
Most reasonable people are offended that a young child was treated in such a physically harsh manner, (abused is a more apt word), by ignorant school officials and then handed over to police goons who handcuffed her and hustled her off to jail.
Recognizing the public outcry...and it is an outcry from reasoned people...Those moronic adults involved have made profuse public apologies for their stupidity.
Here is a case where loss of jobs should be applied and a punitive law suit against those involved instigated.....and I wouldn't be surprised if one isn't in the works now.
She had hidden the scissors in her backpack,
(you chose to use the word hidden as though everything in one's backpack is hidden)
her choice, she is either hiding them, or brandishing them. The sooner she learns she can't win, the safer the system will be.