For grown-ups, spring may signal barbecues, sweater sales and vacations. But for their kids, it's a little different. We've entered ice cream weather, when kids take their own kinds of vacations—to the playground.

    While disguised as magical lands of primary colors, slides and swings, playgrounds serve kids in more ways than dishing out ever-important fun. Playgrounds are where kids exercise, make friends (and maybe even first loves), and learn about risk taking, emotions and community. And while it seems like playgrounds have been around forever, many parents and grandparents can attest that they've changed their look a bit: Edges are rounded. Slides are shorter. Monkey bars are disappearing. What was metal is now plastic. Goodbye asphalt foundation, and hello bits of rubber. These changes are all, of course, in an attempt to make playgrounds safer.