I would not send any toy to preschool that DS would be devastated to lose or break - there are 28 children and 6 staff, which means things happen like that, they just do. Children should not be taking valuable or breakable stuff to preschool.
Ripped clothes I would more raise an eyebrow about, my DS is a demon and very rough&tumble, but we've never had any ripped clothes. But ultimately, I send DS in rough clothes as they do get damaged when kids are playing.
I know it is frustrating when things get damaged, but unless it is happening very frequently, I think that sometime it does "just happen".
That's just kids though! For some reason, my DS is murder on socks. I must buy him twice as many as his big sister, and I'm forever throwing pairs out with holes in. Like several pairs a week, I just don't understand! YY to patching clothes, I use my old jeans and joggers to do his clothes :-)