Here's what I have learned -- and I hope I'll find time to put together a proper post.
Working memory, attention, focus, executive function: all of these faculties are limited resources. Period. In that sense, your brain is exactly like a muscle: fatigue and stress lower performance. (Anxiety lowers performance, too, but for somewhat different reasons.)
If your child is shooting for a high score on the SAT, he or she needs to do two things:
1. Automate everything he or she can automate. SAT Math is supposed to be a test of problem solving, but I am now positive that the 800 scorers are not solving problems. They're getting right answers on exercises they can do 'in their sleep.' In short: overlearning.The reason to shoot for an 800 if you want a 700 is that anything that knocks out mental resources will drop your score by that much.
2. If you want to score an 800, shoot for a 900. Ditto for 700: shoot for 800. Which is another way of saying number 1.
Now I'm going to go crawl in bed.
overlearning by WiseGeek