High school seems to be the major cut off for Aeropostale. Very big with the middle school crowd but not so much with the high schoolers. My DD wouldn't touch Aeropostale all through high school and only this past summer did she buy some underwear and sweatshorts there. They do have great prices.
During high school my DD's favorite stores were the same as your DD's. Fortunately, she went to private school and wore a uniform so we didn't need to much and once we found her sizes and knew how each store fit her, we were able to get stuff on line much cheaper. From now on, get your American Eagle stuff online in their "sale" section. Then, take a trip to Potomac Mills Mall in Woodbridge, VA and go to the Abercrombie and Fitch and Hollister clearance centers. Sometimes they have great stuff.
I just bought my DD a short-waisted parka at Abercrombie. It is down filled, fur collar. Regulary $239 and I got it for $99. They don't always have your sizes in things but they are very reduced from the regular store prices.