This is another fun "game" Toby and I played! I'd throw a treat on the floor and point at it while saying "Take it, take it, take it!" in that deleriously excited voice previously learned for "come when called". Of course Toby was happy to obey. The third or fourth time though I'd say nothing. If Toby lunged for the treat I'd say "leave it". If he waited nicely, after a few seconds I'd tell him to take it as before. The idea was for Toby to learn that he could "leave" things without getting frustrated or deprived.
It was so cute to see him catch on to the game. If the treat fell and there was silence, he would immediately sit as if to say, "It's too tempting if I'm not parked on the floor!" Remember the Peanuts cartoons where Snoopy sits like a vulture staring from the top of the doghouse? Toby stared at the treat as he waited just like that.
Pretty soon I was totally confident in his mastery of take it/leave it. So when it was our turn to demonstrate to the class, for once I wasn't a bit anxious. Mr. Dean told us exactly what to do if our dog took the treat without permission. These were special treats, pig ears or something (I know, sounds gross, but the dogs loved it). I barely paid attention to him because I knew I wasn't going to need to do anything.
Boy was I surprised when Toby lunged at the treat. He had it in his mouth in a millisecond. You'd need a super-slow-mo camera to see it. My jaw dropped and I just stood there. Mr. Dean said something like, you're going to have to be quicker than that to teach him, and I just said, "But he never messes that one up!"
So that night I learned not to assume that everything would go the same way in class that it does at home!