This is in the episode when Mikey wants to be part of the safety club. At the end you see Mikey holding up a stop sign to allow kids to cross the street. Then you see the rest of the gang cheering Mikey on. It then starts to rain and the gang goes inside the school. When the kids walk into the lunch room, Mikey has somehow beat the gang to the lunch room and has already started eating. This isn't possible, because the gang took the one and only route to get there in the fastest possible time and you never see Mikey pass them up.