Some grammatical topics lend themselves to interesting and creative classroom activities. Expressing location using prepositions is one of them.
In my Spanish 101 classes years ago, I used to use an 11” llama (covered in real llama fur, mind you) as a teaching aid. Instead of the sorts of questions and answers in the examples in the book -- “Where is the book?” “The book is on the table”, and so forth -- We substituted “llama” for “book” and it actually kept their attention surprisingly well, simply because it was different. (This was back in a lower-tech era.)
On one particular preposition-lesson day, I came to my 7:30 a.m. class armed with textbook, overhead transparencies, lesson plans and, of course, the llama.
One of the students came in with his bicycle. He told me the lock had been damaged in a theft attempt, and he wanted to bring the bicycle in to class so it wouldn’t be outside unlocked and vulnerable. I told him that would be fine as long as I could use the bike in my lesson. He looked a little confused, but agreed.
By the end of the lesson, I was pretty sure that I had the only Spanish 101 class on campus that could say with perfect fluency, “La llama está en la bicicleta”. (‘The llama is on the bicycle.’)
Unfortunately, the llama's budding educational career was cut short once we got cats. Somehow one of the cats managed to get him down from his shelf and went to work. I came into the room to find three cats hunkered down just like their wildcat predecessors at a kill -- only this wasn't the great African savannah; it was the living room, where they surrounded small piles of sawdust stuffing and a now-headless llama.