I take it that you're not from around these parts.
Like others have said, These are "Writing spiders" or the proper name is Yellow Argiope Spider (I think). Catch a bug and throw it in her web for some entertainment. When I was young I got in trouble for bringing one to school in a shoe box.
There are several on my property right now along with many of the normal orb spiders.
Funny/creepy story: In the 90s I was riding through the woods in a truck with some of my friends. It was night and we ran through several orb spider webs along the trail. I was on the passenger side and had the window down with my arm propped out. I noticed a tickle on my neck and grabbed the area and came off with a handful. It was a large orb spider that has crawled up the truck, through my shirt sleeve and onto my neck. I threw it in the floor of the truck, the driver hit the interior light and the guy in the middle freaked out stomping the spider. I get the creeps just thinking about the feeling of that thing crawling up my neck.
They're just a bit smaller than the writing spiders at about the size of a half-dollar. here's what it looked like.