Tasks are great! They don't have to be large, elaborately planned things. Even more powerful, if they are simple and just about the teacher "getting out of the way". It should all be about students having lots of time purposefully using the English language.
So here are 50 very simple tasks you can do with students. Keep it simple, just tell them what you want them to do, give an amount of time for the task and then set them off doing it.