Apple’s retail stores in Glendale Galleria and Tyson’s Corner will be featuring a free QuarkXPress for Advanced Users session today at 6 PM and 7:30 PM. This Saturday (and every Saturday through September 1), all retail stores will also be featuring a “Give Your Kids the Edge” presentation, which runs every hour from 11 AM to 5 PM. A full schedule of events during the coming weeks can be found here.