As someone who has lived in 6 states I've made it a habit to check out the local Renaissance festivals. This is such an awesome festival. It's only going on, on Saturday's and Sunday's, but it goes on until 5:30pm. Like any fairs and festivals bring cash folks because that's all the vendors accept. There is an ATM there if you forget.
Beers are about $6 (one per person) and food ranges from $6-10. The lines for food are very very long, expect to wait 6-10 minutes. I've noticed the further away from the entrance the shorter the lines get. The admission is around $23 for adults, so between admission and food you can expect $50 for one person. It's set up like a village there are tons and tons of shops but a lot of things are over priced.
There are two jousting shows throughout the day and tons of other little side shows and performances. Expect big packed crowd the entire day. Parking is free of course but finding your car may be a little tedious depending on how far away you parked (and how much beer you had to drink).
There's tons of stuff for kids to do there it's just a fun family friendly event that you can do the entire day. It's a little pricey but it only comes around one time of year so it's worth it.