The teacher writes down a three diget number and does not let the kids see what it is.ex: 267 Then the teacher picks kids to say a three diget number. If the kid says 368 the teacher would say pico because the kid got one of the numbers right. If the kids said 321 the teacher would say fermi because the kid got one of the numbers right but it is in the wrong place. If another kid said 267 the teacher would say thats right. Lets say the teachers number was 597 and a kid said 592 the teacher would say pico pico because the kid got two of the three numbers right and in the right place. If the teachers number was 209 and a kid said 902 then the teacher would say pico fermi fermi because fermi means the kid said the right number but it is in the wrong place, and pico means the right number the right place. The kid who says the right three diget number wins and gets 3-5 extra credit points.(It's up to the teacher to decide how many the kid who wins gets).