Why are we teaching this stuff?

Here's a great post by James Lang that will help answer a student's question: Why do I have to learn this stuff? His suggestion to put rationale at the top of every assignment is not new - especially not new to K-12 teachers who write detailed lesson plans for every class. But it is essential. If we cannot answer concisely and cogently why we are teaching what we are teaching, then probably we need to think more deeply.