Color War!

I was fond of the series when I was a kid,and I thought that this was a fun book. The girls in Cabin 6 at Camp Sunnyside typically all end up on the same team in the camp's annual color war. Only this year, a couple of the girls are assigned to a different team, splitting the cabin into different factions. The girls become competitive, and the pressure to win puts a strain on their friendship. Before the war is over, the girls have to decide which is more important to them: winning the war or remaining friends.