I never seem to have enough kid birthday cards when I need them. Stampin Ups "Bugs and Kisses" set can be easily be adapted for a boy or a girl based on color scheme. Here's my boy version of a full (4.25 X 5.5) card. I hope to post a girl version later today.
Stamps: Bugs and Kisses, Canvas BG
Paper: Pumpkin Pie, Brilliant Blue (WRAK gurlsofgrace), W. Wasabi, White
Ink: Brilliant Blue, Tempting Turquoise, Wild Wasabi, Rose Red
Accessories: Pumpkin Pie Grosgrain ribbon