X.O.
Are they into baseball? A friend of mine is trying to visit every MLB stadium, so each summer he plans a trip through a region and hits all the stadiums & attends a game at each along the way. For example, in Chicago you could do Wrigley Field (Cubs), US Cellular Field (White Sox), swing up to Milwaukee for Miller Park (Brewers), and then perhaps along the way throw in some boating, fishing, exploring downtown Chicago, riding the subway, etc.