1. Speeding up computers. Removing spyware/uninstalling programs people don't need is always in demand. 2. Making websites for local businesses that don't have one yet. In high school I traded a website for a cake a month from a new cake shop. The cakes were better than money! 3. Backup solutions for offices. It's difficult to back up Windows computers properly. Most businesses are not backing stuff up properly and they know it. They'll pay to have someone tell them what to buy/subscribe to and then set it up for them. 4. Carpet cleaning. Do they live near condo towers? Lots of demand for that. Not too hard to do. There are lots of non-tech businesses that teenagers can do too.