First off, let's talk about the obvious one: chocolate. Now, I know you remember the chocolate fundraisers back from when you were in high school yourself, and you may think that this is an old, tired fundraising idea for high school that just isn't viable anymore. But that's an incorrect assumption. Chocolate fundraisers are as popular as ever, and in fact they're still around for that exact reason - because chocolate is as popular as ever. How many people do you know who don't like chocolate, or who wouldn't fork over a dollar to buy a delicious $1 chocolate bar? Enough said.
Pizza cards are another good fundraising idea for high school. You can make a huge profit (up to 90%!) using pizza cards, if you anticipate a large number of sales and can commit to an upfront investment of at least 1,000 cards. The way this fundraising idea for high school works is that your supporters pay $10 each for the cards, and this entitles them to a a two-for-one pizza offer at a local merchant. $1 of the card price covers the cost of the card, and the rest... the rest goes directly to your high school. Even when purchased in smaller amounts, pizza cards still have an impressive minimum profit of 50%. These are both fundraising ideas for high school that you can really get excited about.