While...

 
Landscapes... beautiful ones can be a good teaching material. They can help you recreate an entire universe and make your students actively use English without even noticing. First, select at least four or five landscapes and stick them around the classroom : e.g. desert, beach, forest, meadow, waterfall, etc
Ask your students to choose their favorite destination and have them stand near the selected landscape. Then tell them to close their eyes and imagine 2 or 3 activities they are doing in that very moment ("I am searching for water in the desert"; " I am picking flowers on the meadow"; " I am listening to the birds in the forest"). Taking turns four or five of your students should tell an activity they're doing and also pay attention to the others' stories. Then the teacher asks : "What are you doing while Mary is picking flowers?" and they answer using as many activities as they can remember.
Thus you can teach Present or Past Continuous making use of your students imagination. Further more you can even ask your students to "create" their universe giving a name to their land and have them imagine their routine in this realm. Then they should confront their worlds, compare them by saying "while I was riding my unicorn in Catatonia, John was flying his space shuttle in Neurobia". After they have already created their realm you can practice as many grammar and vocabulary topics as you want, such as type of houses, people description, their daily chores, rules(using modals) in their worlds...
Try and let me know if it works :)