One of my personal techniques that I use in the class room is what I call the "No Fear Rule" This rule is simply this, I tell the students on the first day "Do not be afraid to learn" What this means is that if there is anything in my presentations to the class that they do not understand, ASK! If I find out you did not know something and did not ask, I will remind you "Do not be afraid to learn" Of course through expierence I know what they don't know, and I will wait for a question from them after presenting them with some information. If I do not recieve any questions, I will anounce "Well if there are not any questions, I must assume you understand the subject completely" and then I will pick on a student at random and challenge them with a question they should have asked. This will immediatly put pressure on the student to answer, but I give them just as fast an immediate out, I will say, "and if you don't know, just say so" I will then pick on several more students until finally someones asks me the question. "AHH, I am glad you asked, let me explain" This now just turned into a game for them. I find that this technique places pressure on the student (challenges the student) with out stress and forces them to ask more questions to understand the material. Once they understand, when it comes to test time, they do well by their own merit and when the succed, their stress falls away.