Asking Questions

I've yet to fully crack the how-to-get-students-to-ask-when-they-don't-understand nut.

What I really like about a discussion-based (Harkness, Socratic) classroom is students talking and sharing. It's well-documented that real understanding is demonstrated when you can teach someone else, and the discussion-based method approaches this ideal far better than most.

That said, some students simply won't ask questions when they don't understand something, despite:

1) my emphasizing daily that mistakes are welcome and how we learn

2) my making mistakes and letting everyone know that I made a mistake

3) my asking questions when I don't understand something

4) thanking each student who asks a question

5) thanking each student who shares a mistake

6) providing (or attempting to provide) a classroom environment in which everyone is supportive

The struggle I have is between this being OK and how frustrated I feel when a quiz/test grade is low, as I want all of my students to succeed. I mean, part of learning is learning how and when to seek assistance. And part of learning, a BIG part, is failing.

On the plus side, no one is able to remain silent in my class. Each day, at least four students stand in front of the class and speak/present and I rotate through all of the students. But, how to get questions when something's not understood...