Another colleague and I have had a similar concern. We had students coming into Spanish 3 classes from various teachers from different schools. Some of the teachers stressed proficiency and their students were "speakers," and could handle improvisational tasks. Other students were used to doing "worksheets," and not speaking. Those kids could conjugate a verb in a fill-in blank, but could not utter a sentence or form a question with the same verb. The speakers also handled writing and reading tasks better than the "worksheet kids" as they were "speakers."
What did we do? As in the past, we changed our seating charts monthly and paired one strong proficiency student with the weaker one. The proficiency student informally helped the weaker student build his skill set and clued him in on how to do the activities.
We used a class set of index cards, too. Every student's name was on a separate index card.
As I mentioned above, we did a high/low pairing of students .... i.e. that was your assigned seat partner for the month. For variety, we did lots of pair work during a class period. Using the index cards, we would pair students high/low for various pair work activities during the period. So... all the students had an opportunity to get up, move around to a different temporary partner for pair work. Using your set of index cards, you can easily pair the high/low kids .... like a match up game with your cards. (You're "rigging or fixing" the pairs.)
Of course, several of the non-proficiency students were linguistically bright, quickly improved, and caught on; so, our class sections improved. Those bright ones quickly realized what they had been missing in their "worksheet" classes, and wanted to get themselves up to speed with the "speakers." Oftentimes, you will notice that some of your best speakers are not always your top A students.... those proficiency kids are risk takers and enjoy "doing something real--like interpersonal communication" with their classmates than doing endless worksheets.
So... try a lot of heterogeneous pair work within the class period. Get the kids up and working with different individuals. Use a monthly seating chart with monthly assigned partners. I think this low-tech, student-centered approach will help you "homogenize" the process.
Best wishes! Buena suerte!
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