Is it possible to pull off a wart?

Oh, my goodness, don't do that. You should talk to your doctor. A wart is a skin eruption, and pulling it off will leave a wound that is open to infection. It's probably not even likely that removing a wart this way would leave the skin clean from the agent that caused the wart. Talk to your doctor, or school nurse, or use an otc preparation if you are sure that the one you get is appropriate for the wart you have. Decades ago, I treated a wart I had with simple saline (water saturated with table salt) and it turned white and disappeared within several days.