what is this movie!?!?

ok i saw this movie (this is gonna be hard) it about these teens who dare each other to go into this old abandon hospital and they go in, some die, and they see this ghost little girl with a red ball..... idk if this is clear or not, probably isnt, but plz help!!!!!! it is bothering me!!!

OH also another were this family moves into this house and in the basement is alot of ghost ppl and the only thing that can protect them from the ghost ppl it this wall that they carry around...., and they put up the clear wall once and this ghost with crazyy hair that screeches and has nails trys to scrach in but it cant!!! so plz help if ANY of this made any scence...... :) so much appriciated!!!!