Kahoot! is self-described as “a game-based platform that makes it fun to learn any subject, in any language, on any device, for all ages!” With a FREE account you can create quizzes and competitions which 4-H members can answer on their cell phones and other devices. This site has great potential for livening up your meetings, helping with judging team practices, and more.
Check out this Kahoot! informational video here.