legally you cant babysit, wash cars etc. if you get paid for it, because you are not registered for tax and NI. The only job i can think of is paper boy/girl. I worked over the summer holidays when i was 15, i had to get a work permit from the council, could only work a certain number of hours, had to have loads of breaks and could only work for 4 weeks in a row, but it was a lot of messing about for myself and my employer. I think they only went through with it because my dad worked there.