If you were interested in something a bit more engaging, I have students who namely speak Chinese-They would love the cultural exchange side of it and Edmodo is an excellent website that we can use to establish contact between the groups in a moderated manner.
What if the exchange was regularly in English but each class needed to set up a language lesson for the other in regards to their native language, teachers would particiapte in the language learning and this would be more of the work habits mark where as the English interaction would be the language based portion of the mark.
Check out some of my previous ideas here:
https://www.teacherspayteachers.com/Product/Pen-Pals-Teacher-Documentation-and-Class-Handouts-French-and-English-4334256
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