I found a great tutorial to turn a photo to black and white and then colorize only a portion of it. I really like how it turns out.
Essentially you create a new layer, make it black and white and then erase any area where you want the under color to be exposed. In this case it was easy because my son's t shirt was already black so I didn't have to be too meticulous in my erasing. Give it a try.
here are some tutorials
http://www.digiscrapshak.com/index.php?categoryid=7&p2_articleid=15


