Personally, I'd stick with a white tee shirt and jeans or something like that. We don't usually do prints in professional photos, and I've never done a print on my son. My kids generally wear the same types of outfits in their photos each year, but I like the children to stand out, not the outfits. I think my daughter's worn a white dress in at least 3 shoots and my son's probably worn 3 variations of a white shirt and 2 of a blue shirt. I'm always very happy with the photos. Good luck!
Annie ~
Mom three Junebugs: 9, 7 and 3