As a new owner of a 11inch 1.6/4gb/128gb... and a 13inch base macbook pro 2.4/4gb/etc...
For a highschool student, and wanting to use it for a while, I'd actually recommend the macbook pro, expecially if it's your main machine for a while.
Here's my reasons, you can take them and decide if they apply.
MBP = more battery life. Says 10 hours, I get a realistic 7-7.5 doing what I do, which is amazing for a laptop, and good on the go and not have to worry about adapters and charging.
You're going to get less with either air.
The processor in the mbp is going to be faster, and the non proprietary/soldered on parts means that if you do need 8gb of ram in the future, it's as easy as popping it in. Same with the HD, you can get a great SSD and just plug it in basically.
And finally cost. If you happen to live somewhat near a microcenter, they have the 13 inch macbook pro for 999$... which is a great deal.
If weight and looks are the most important for you, the MBA is a sexy machine.
If you're going to have a laptop you will use for years as a primary machine, I think the pro is a better choice.