If you think adult opinions vary on what makes for good art, ask a child and you'll find a whole new level of discerning taste.  Although kids tend to know what they like when they see it, opinions can and often do change in a hurry.  As such, art for children is best realized when offering immediate gratification but also possesing a level of depth that can't be fully realized within the first glance.  Well executed art grows with them and their ever increasing ability to appreciate the nuances of form and color.  It never falls out of favor, even with the youngest of critics.  Browse some of my personal favorites for boys, girls or either in the categories below.