Walking with kids on a field trip, I observed that they will always be 20 steps behind you. I urged the leader to speed up, as he was walking at a snail’s pace and clearly was frustrated (being the fit and healthy guy that he is). Sure enough, the kids sped up, but were always 20 paces behind.
I wonder whether we slow down and cover less material only to have the kids slow down too. Will they always be 20 paces behind? I plan to have the same argument as last year with my principal, when I continue to accept work from the first marking period after they close out the district grade-book ( because I know how to run a spreadsheet). He did not seem to understand the argument that I don’t mind if the kids learn it in September or December, as long as they learn it. It seems to fly in the face of U.S. High School philosophy.
Meanwhile, I have started the Corusera “game theory” course that was sent as an advertisement after Jo Boaler’s course. I’m drowning. Clearly, I am not about to become a master manipulator. Drat. I have already given up any idea of getting at least 70%, and that’s only after the first problem set.
crazedmummy 
Your question about the 20% behind makes me think of a recurring argument about how high to set the bar in certain classes. I have long been convinced (I think it’s a sign of optimism coming up) that kids WANT to move toward the goal line. If you hold them to high standards it is true that not everyone will hit those marks. However, if you lower the expectations I think that the same kids might miss the mark anyways. Using your 20% as an example, maybe kids are willing/able to do 80% of what I ask so I should ask for a BIG 100% goal rather than a more modest one.
I know that when I lower my standard, I’m just more frustrated when kids still are not able to demonstrate the most basic of understandings. There is probably a function that relates frustration to learning expectations. Not sure what it is. The Game Theory class has me interested. I bookmarked it and might give it a go. It is free after all…