WOW very bold I am sure HS kids will love it.
As for how much to charge that depends on alot of things. How well off are the parents? Is this for parents or the kids?
We did 2 raffles at my old school the one that was $3 a ticket didnt raise any money but the one that was $1 was a hit, but the parents were from a very poor neighborhood. The teachers did ALOT from their own pockets and most felt they got back more than they gave.
GOOD LUCK I hope yall raise alot of money.