Congratulations to Roberto C. of the 7th grade for suggesting this problem and to Roberto and Jonah W. for solving it. Jed of the 3rd grade suggests that the team can leave 9 seconds for someone to guess the opposite color if she sees three identical colors. After 9 seconds, if no one has volunteered, then the hats must be 2 of one color and 2 of the other. In this case, anyone can volunteer to guess the color that they only see one of. This strategy will be effective 7/8 or 87.5% of the time.