Write a message on your post-it suggesting an activity with your classmates to practise your English. Here are some ideas:
*Meeting in the school café to speak English (or while you walk, on the river garden)
*Meeting to watch one of the OLS films (OLS=EOI)
*Meeting to watch a film at home
Now take the seat to your right and read the post-it your classmate has left. Write an answer in a new post-it with contact details if necessary and leave it on the desk, next to the first one.
When you are done, return to your seat and collect the two post-its. You may contact your classmate after class, if it is convenient, to practise your English. Enjoy!