Jeep Offers

I’m currently half way through Year 10 at school. In the summer holidays after I have finished Year 11 we have a 4 week school trip to Kenya. It will compromise of volunteer work, wildlife conservation, a safari and scuba-diving. This is a once ina lifetime opportunity and will look great on my CV however, in total the trip cost £3450 and is to be made in three payments of £1150. I have several ideas including:

-Selling sweets, chocolate and pop at school
-Car boots
-Washing peoples cars
-Raffles

I feel this is a great start however I need some more ideas, thanks in advance.