My DS is 18 months old and is getting upset when he can't do things right, so stacking blocks he will do it and then if he picks up the wrong one and it won't fit he turns to me and moans 'Mummy' getting cross that he can't do it. Playing with his animals for instance if he's trying to stand them up in a little house and knocks one over he gets cross.
I was wondering how best to deal with teaching him that he can do it if he tries again, and that not everything goes right first time. Obviously he's young and he doesn't understand yet how things work and a lot of frustration is there now when trying to do new things.