We realised yesterday morning before school that we were supposed to choose an item to send in (Y4) for a project about the Arctic. It was supposed to be something for ds to take with him - smaller than a child's shoe box and it didn't way what it had to be - sentimental or useful, I think were the vague parameters and not of value as it would be on display all term.
We cast around for something and turned up an old 'toy' of ds1's which is a clockwork spark maker.
It's not dangerous - though obvs you have to keep it away from flammable substances like petrol, gas etc - and I thought it was basically a toy and the display wouldn't be within reach of the children, or at least that the items wouldn't be played with before being discussed with the teacher in terms of what they were and why they had been brought in.
Ds told me the display was actually put on a low table well within reach and his little friend took the sparking device and was playing with it yesterday - so not having direct contact details for the teacher, (you only get an option for the office and it's a huge school) I told him this morning to go straight to her and explain that maybe it ought to be put out of reach for now.
(I had also googled it, we were given it as a gift, and found it isn't exactly a toy, ahem) 
He said he didn't get a chance as it was already on her desk, and according to his friend, she had taken it away rather crossly remarking that it should not have been brought in.
I'm not sure what to do now. I'd like to apologise to her but honestly I misunderstood - and she didn't tell off ds - and he still hasn't spoken to her about it - so I assume I am in trouble and he isn't. Which is fine but would you go in and explain, or just leave it?
Am I a complete idiot?
It's not like a cigarette lighter - it contains no fuel and produces a pretty sparky effect but would not burn anything even if you wanted it to probably.
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