Yes 16 year olds are definitely able to work I started at 14 on saturdays with a work permit. Don't think they need them at 16.
Hairdressers are always looking for 16 year old juniors for Saturdays and also small independent cafes are worth a try.
Places like chessington world of adventures mainly hire youngsters and have a range of working hour contracts. Also look at leisure centres they hire teenagers for helping with children's parties.

Hope you manage to find something!

Does anyone know if 16 year olds can work ( I mean a Saturday job while at school ) . My daughter has tried a few places but they all seem to insist on 18+. Any suggestions of local places who welcome a helping hand - and pay ! We've already done volunteerring.