Our daughter's first laptop was a Dell Latitude and it worked very well for her. It still works but it is just full and slow now. It is used as a back up if needed somewhere in the house.
When she started Sr. High school (11th grade) it was evident that she needed a better system. Her AP classes all but require a personal laptop, they take them to school to use as well with some of the classes. We got her a MacBook Pro (out of your stated price range) and it has been a great little machine for her. She is in her Sr year now and she still uses it a LOT for school work.
I have a Dell XPS 14Z that came out last year. I love it. I run my company financials on it thorough Quickbooks and it is a great machine. It still is more than your stated budget.
You can get cheaper Dell's. Possibly look at refurbished machines and see if you can get a warranty with one.
At 11, he will start using the computer more for school.
Good luck.