Teenager leaving straighteners on!

[hugoagogo]

dd frequently worries she has left her straighteners on and texts me to check.
So far she hasn't and all is well, but I am not always home.
Short of taking them away from her, is there some gadget I can get that will mean she can't burn the bloody house down?
She has a wee heat proof mat, but I don't think she uses it.

I used to phone my mum from school to check I'd switched off my tongs, straighteners were invented then but it was the start of my OCD so please keep an eye on her incase there's any underling issues.

I always used to stress that I’d left my hair straighteners/iron/oven on (even though I’d have checked several times before leaving the house). So now, just before I go out, I unplug everything and take photos on my phone of the empty sockets. It works really well, and it’s a habit now so I never forget to do it.