Funny you should mention that. He and I chatted about it last night, spurred by this thread. He's actually considered a group points system as well
It would all be one big group, to help promote class teamwork, but the concept is similar. Example : If 5 people get a perfect score on the quiz, everyone in the class gets +5 points to their total class grade. Or if no one gets an F on a test, everyone gets +10 to their overall. Even the smartest kids can't get the maximum points without helping their classmates. And the kids who don't do as well feel good when their peers succeed. (these points would be extra credit, of course)
His next step is more advanced bonuses, derived from Video Game Power-ups. Whoever gets the highest score on a quiz earns a class-wide autocorrect power. They can pick a question on the NEXT quiz, and using that power makes it count as correct for the entire class. "everyone got question #5 wrong? Use the power, and now everyone got question #5 right!" -OR- The first student to reach the point threshold for a B grade gets full credit for the rest of the homework and doesn't have to actually do any of it, or turn it in. (given the point-count system and weight of the Final... a perfect grade student would only reach this threshold near the end of the semester anyway, so not a HUGE deal, but still it's a goal for the kids)"