I would take out a good handful of toys that are not trashed, hide them. Let him trash the rest as he wishes. DO NOT give him any more. When he has a fit simply state, " You didn't respect your toys." After a little while talk to him how he could show you he is ready to be a big boy and respect his toys, have him help come up with ways to earn some toys. THis will help foster respect and appreciation. Also start teaching him to put his toys away each night. You will have to show him and break down how exactly he is supposed to put his toys away, this will also help.
at 3:24 PM on Oct. 31, 2010