Dear Mark: Adding to Allen Ascher's great reply (which  I think is  very helpful in getting students to understand the function  of nouns,  and then, by extension noun clauses), here's another  suggestion:

Although some teachers might consider the use of the  students' first language in an English classroom heresy, if YOU  don't,  you might consider pointing out to students the equivalent  structure in  Spanish. (I'm assuming all your students are Mexican and  therefore  first-language Spanish.) Since the noun clause in Spanish is  very  similar to the noun clause in English, both structurally and in   meaning, giving students an opportunity to compare might be useful.

I  third technique that can also help reinforce noun  clauses is to relate  these to indirect speech when you teach that, since  indirect speech is  essentially a kind of noun clause. By using a  variety of techniques  students will develop confidence and will  understand and use noun  clauses accurately and fluently.

Hope these suggestions have been useful.

Joan

If you want to draw attention to patterns in L1 and L2, you can present two or three examples of the pattern in L2 and ask the students How would you say this in your own language? In a class where all learners share a common L1, learners might write the L2 and L1 patterns one above the other and then draw WORD > WORD links. This can be useful to show differences in word order.

Even in a mixed language class, this technique can be useful in helping learners to understand and make sense of new patterns.