This New York magazine article about praise is full of educational psychology ideas for teachers. I hope you'll read the full article, but my takeaways were -
Praise for effort rather than intelligence or even results.
“Emphasizing effort gives a child a variable that they can control,” she explains. “They come to see themselves as in control of their success. Emphasizing natural intelligence takes it out of the child’s control, and it provides no good recipe for responding to a failure.”
To be effective, praise needs to be specific and sincere.
New York University professor of psychiatry Judith Brook explains that the issue for parents is one of credibility. “Praise is important, but not vacuous praise,” she says. “It has to be based on a real thing—some skill or talent they have.” Once children hear praise they interpret as meritless, they discount not just the insincere praise, but sincere praise as well.
Teach that intelligence can be developed.
The teachers—who hadn’t known which students had been assigned to which workshop—could pick out the students who had been taught that intelligence can be developed. They improved their study habits and grades. In a single semester, Blackwell reversed the students’ longtime trend of decreasing math grades.
The only difference between the control group and the test group were two lessons, a total of 50 minutes spent teaching not math but a single idea: that the brain is a muscle. Giving it a harder workout makes you smarter. That alone improved their math scores.
The brain has to learn that frustrating spells can be worked through. “A person who grows up getting too frequent rewards will not have persistence, because they’ll quit when the rewards disappear.”
That intermittent re-inforcement idea is particularly important in developing persistent behaviour - it's why you check your e-mail too frequently and why gamblers in Las Vegas continue to play slot machines.