Nick Paff, 8, throws a bean bag in a game of cornhole with Garret English at the 50th anniversary of the Gaiser Center party Wednesday. The Ellen O'Brien Gaiser Center will continue to mark its 50th anniversary with a meet-and-greet Thursday at its 165 Old Plank Road location. Catered picnic food, disco music and giveaways are planned from 3 to 7 p.m. Staff and board members will be on hand to greet visitors. Shuttle service is available from Butler County Community College to the center.