With my mixed level classes I love story sequencing and story puzzle activites.  I choose a series of pictures that go with the vocab I �ve been teaching.  Then I give my advanced students a list of words they should use to write captions for the story.  I give my intermediate students mixed up sentences to unscramble and write as captions.  The lowest students get prewritten captions that they have to match to the pictures and then copy.  This keeps them all busy with the same vocab but allows them to focus on different tasks.