This year for my son's 5th birthday he wanted a Knight party.  We ordered Knight partyware and helmets from BirthdayExpress.com. We used red tablecloths with red and purple balloons for decoration. I made a castle out of a large box by painting it light grey and sponging bricks with darker grey.  For a craft I bought yards of different color felt (approx. $20 for all of it) and made simple tunics for each of the children (a 1' x 4' piece folded in half with a hole cut for the head and different ziz zags or scallops for the hem line).  I also trimmed the neck and hem line of each tunic with cording ($.33 for 10 yds) and a glue gun. I cut crests out of sticky-back felt.  The kids each designed their own crest with pieces of felt, gems and pearls. The parents helped hot glue the gems onto the crest. When the crest was done it was stuck on the child's tunic. With the felt scraps I made simple banners to hang around the yard.  Each child was given a foam sword and a small pouch to attach to his belt (a piece of thick yarn cording). After everyone was fully outfitted we started our Tournament of Knights. I made jousts and javelins out PVC pipe and colored them by adding colored electrical tape.  We had three games: Throwing the javelins through hula hoops, riding stick horses and spearing a small ring hanging from a pole and a bean bag toss to save the princess.  I painted a castle and dragon on a board with a hole in it. The bean bags were small crests made out of felt and hot glued together.  Each time someone completed a task in the tournament he received a gold coin for his pouch (no prizes for the winners, everyone won). We made Knight Punch (sherbet and Sprite) where each child helped pour the two bottles of Sprite into the punch bowl on top of the sherbet (this was a big hit???). I used paint pens and colored "gems" and gold squiggles on plastic cups for their punch. We ordered pizza and had cake. I made a castle cake out of four 8" square cakes. Three piled up and the fourth cut into quarters. Using three of the four quarters I piled them on top.  Frosted the castle with light grey frosting.  I frosted four sugar cones then rolled them in red sugar and put them upside down on each corner. I trimmed the top of the cake with gum drops, and used black frosting to make little windows all around the castle. I set the cake on a foiled covered board and sprinkled graham cracker crumbs for dirt and blue frosting for a moat. It really came out better than expected.  This was a very fun party to plan and was really very inexpensive. The kids had a great time and the parents were excited because all of the boys ended up with a Halloween costume.