What are some good reasons to join online school im making a slide show to show my parents

One reason is because u will be willing to learn in the comfort of ur own home and wont have to travel every morning

You can do schoolwork at your own pace, without the distractions from other students. You can sometimes (depending on what online school you're considering) customize your school to fit you better, play at your strengths and work on your weakness. If you have trouble at math, than you can spend extra time there, or if you're great at english, you could spend less time working on that, while in a regular school you have to work in the time that the teacher gives you.