I will try to help but need some more information. Does he say that he is unable about being a boy and does he want to try other activities which are generally more girl-like (i.e., play with toys rather than boys toys)?. Is he driven to (obsessed with)
get these things?
Sorry, I meant ....unhappy about being a boy and wants to be a girl instead.
and play with girl toys rather that boy toys,,
I apologize as I was in too big of a hurry when I asked for more information. I have some time now and want to address your concern. If he is displaying the other symptoms mentioned above, he may meet the criteria for a diagnosis of Gender Identity Disorder. If this seems to be the case, then individual and family therapy is recommended to help him live and adjust to his gender and give parents support and suggestions for responses to the confusion.
If he is not exhibiting the whole spectrum of the disorder, then, having a low key approach is probably best. Mildly saying things such as "These are girls clothes, not for boys" and leaving it at that without too many words and no punishment. You want to avoid having the behavior become a way to get attention.
I hope this helps. There is a good explanation of Gender Identity Disorder in children on the WebMD site. You can also search for the DSM-IV criteria for Gender Identity Disorder.