Given there ages, I think I would choose HS. Especially if they love Toy Story. My boys loved the ride at that age, and still do. Haven't heard anything on the new stuff yet, but even if it is not living up to the hype, I think seeing the characters and theming would be amazing for them. Allears.net has a lot of good info to skim through on the attractions. Are they into Star Wars? If so, they would love Star Tours and the night time show is great. Plus just seeing the Storm Troopers is very cool. I think they may even have a daytime show with them know.
Cool things non-zoo you would "miss" at AK: Tough to Be a Bug, Safari, rapids ride, new Avatar section (not sure if there is height restriction on FOP?).
Donna
Mom to JT 1/03 and TJ 8/04