Under the Sea For my daughter's fourth Birthday Party (Large group hall or area indoor Party).  My family is huge so having birthday parties at home with one bathroom makes it too uncomfortable so we rented the local firehall down the street for this event. Personal note I began planning and collecting little things at dollar stores and party supply places four months in advance. A good deal of the games and crafts were home made which made it less expensive. First I took blue and green crete paper and covered the exterior of the overhead floreccent lights so it gave the room a water appearance. Then I took blue and green table clothes and covered the ten tables.  As centerpieces I used shells that I had purchased from the dollar store with multicolored balloons attached. In one corner of the room I placed our Strobe facing the wall so it would reflect but not blind people just to lend to the twinkle in the water. Then I placed a large storage bin filled with water and ziplock baggies weighted down with prizes and loops attached for a fishing game everyone is a winner.  Then in the other corner I had premade stuffed bodies for the kids and there parents to make their own scarecrow as a bonus favor. I asked the kids to bring old set of clothes for this purpose one per family and we supplied the straw and faces. (My daughter's birthday is halloween, but I never celebrate it that day, it's just too busy for us.)so that honored the halloween spirit of her birthday a little out of context but it worked and helped get everyone involved. Then set up close to the center but near the wall, we had a kiddie pool filled with sand and buried tresure. As a final game, they found necklaces and other odd toys in there.   We only allowed one treasure per child. Once they found something they had to take there bounty and go.   Plus we had a fish pinata that was torn to pieces after the cake, ice cream and presents were finished. Needless to say this was a very busy day but not a bored person in the crowd and everyone had multiple prizes.  It's hard entertaining large groups of various aged children this was a success.