ATLANTA -- The fifth annual Rivals100 Five-Star Challenge presented by Under Armour is underway at the Georgia Dome, where 104 of the top high school football players in the nation will compete in two sessions on Saturday. From 9 am to 1 pm ET, there will be a skills and drills session, followed at 6 pm by a 7-on-7 tournament and Big Man Challenge. Keep refreshing here throughout the day for the latest vines, photos, tweets and more.

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