For April 1st Max needs to invite his friends out to do some sort of activity (like paintball, go karting, bowling, rock climbing, etc), have a camera crew there and do whatever he can to seem suspicious and make them think there's a twist...only for there to be no twist. Just a nice day hanging out with friends. Except the entire time they're anxious to find out how he will mess with them
Actually I once had the same feeling as those guys: I was Go Karting with some friends from school and a girl had problems and decided to quit the race. But luckily she returned and suddenly was much faster the the rest of us. It turned out that a technician from the race track had taken her place. π