[slayed0]

Not asserting fact here but merely providing my interpretation:

The engineering teacher may have advised the student to bring the device to school but to not pull it out in any other class. This could have been done to avoid distracting other students or attracting unwanted attention from other teachers. This seems like a straight forward request that may have been taken out of context. I have not seen a quote that uses the word "hide", which really changes the connotation of the statement. I highly doubt the engineering teacher thought specifically that the device could be seen as a bomb.

[zaphar]

I was thinking of this quote from the article:

    the teacher recommended he hide it from the rest of the staff. 

However it's not a direct quote so I don't know the wording the teacher used. Regardless, this teacher seems to have known enough to step in at any time before this child was escorted from the school in handcuffs.

Perhaps he did and was shot down. I don't know but the details as shared stuck out to me.