Wet school bag

When I got to the school this afternoon, my daughter's bag was wet from the rain(making her books wet as well) , when I asked what happened she told that Teacher Pontsho told them to leave the bags there, went back to ask exactly what happened they all didn't know what happened, Until Teacher Pontsho said she told the kids to bring the bags inside, she was making a lot of noise not wanting to take accountability, according to her it was my child's fault that her bag got wet. My thing is:Why did she not make sure that all the bag were inside, are they not supposed to make the last sweep? Were they rushing to get back to their chit-chat ting. I'm a paying for a service, she should have just apologized for her negligence instead she didn't want to take accountability. I had to walk away as she continued screaming. I'm really upset.