I'm a primary school teacher of 20+ years.
To comment on older children, I've had work experience children aged 15/16 coming into my classroom for years. Without fail they've been helpful, polite, keen to get stuck in and enjoyed being with the kids. They've been a real help and a pleasure to help them on their first steps to a career.
In the last two years I've had approximately 8 work experience students.
Only two lasted the full week. Excuses included boredom, tiredness, can't get a lift, saying their mental health couldn't take it. One couldn't leave their phone alone, another said they couldn't come on the bus due to not being allowed and most of them looked purely bored and irritated by the whole experience.
Whenever I asked them to do a job like help a child do up or a coat or sharpen pencils they looked visibly annoyed and did so grudgingly.
Only one showed any initiative at all despite me saying frequently how I welcome them getting stuck in and giving lists of jobs to do if they got a second.
Now I have refused to take any more work experience students as filling in the long forms at the end of their time was also becoming cumbersome and I have a large class of 6 years olds to teach.
I don't know what has caused this very recent shift.