This activity is a fun way to practice classroom vocabulary, the verb estar, and prepositions. I made a list of 20 items (tape, pencils, teacher, etc.) that students had to describe the location of. Before the students came in the room I set things up in really random spots so that they would have to search for things and use a variety of prepositions. I even placed myself in odd locations since I was on the list, too!
You could easily make this a game in which the first student to finish all 20 items received a prize or the student with the most descriptive sentences, etc.