For my daughter's eleventh birthday, we planned an Ocean Adventure party. For decorations: We purchased the Ocean Adventure themed tableware at Party America (You could substitute with different shades of blue solid tablecovers from a party or dollar store) and covered two long tables that ran down the center of our family room after we removed the furniture. Each table had glass candle holders with flickering battery operated tea lights that you can pick up at Michael's Craft Stores. This gave it a fancy ocean themed restaraunt look without the fire risk. The walls were covered with ocean scene setters and 5 foot long sharks, killer whales and dolphins were added. From the Ceiling, we hung streamers in shades of blue going length-wise to resemble waves. We then added inflatable dolphins that we purchased at www.deadmentellnotales.com as well as tissue paper tropical fish from Party City. (You could make your own too). We twist tied streamers in shades of green with fishing line from the ceiling and weighted them to the grounds with fishing weights, then long skinny balloons in shades of green and yellow were added to give it a sea weed type look. From different corners of the room, we tied together white pearlized balloons with fishing line from the ceiling to look like bubbles. The entrance to the family room was made by cutting and shaping large sheets of foam that you can purchase at Home Depot into the shape of giant coral. It was then painted with H20 blue and green shimmery paint. Fish were added to polish the look. We hung tiny blue Christmas lights around the ceiling to add color, light and just enough elegance to make my 11 year old's party a little more grown up. She loved that. We brought out her aquarium which bubbling sounds and fish added just the perfect touch.  For ambiance: We purchased and played a CD from ebay that played the sounds of dolphins and whales and on our large screen tv we played a DVD of an Ocean adventure. We muted the sound on the television so the only sounds you could hear were the sounds of the ocean life. (The children aged 9-11 absolutely loved this).  For food: My daughter chose pizza and a make your own sundae bar. Ben and Jerry's has an Ice Cream called Fishy Food that is perfect for this. We also had out goldfish crackers and gummi sharks and fish along with traditional party snacks.  For the punch: I used our four lighted tiered party fountain and combined 7-up, lime sherbert, blue rasberry punch concentrate from Smart and Final and added dolphin shaped ice cubes I had made by pouring blue raspberry punch into chocolate molds which worked like a charm. This was done several days ahead. For entertainment: We played blind shark draw. In this game you try to draw the best shark you can without looking at your paper. This can be done by blindfolding the artist or holding a paper just under their head so they cannot see. The children as well as adults loved to watch and do this game. It is great fun to see how funny some of the drawings turned out. You could do any sea creature or change this game to suit your own theme. Next we played, a game called carving sand castles (which is also known as the flour game). In this game a small cup is used and flour is packed into it and then it is turned upside-down on a clean sheet of wax paper The cup is then carefully removed resembling a sand castle. A clean dime is then placed on top of the flour. Each person takes turns using a small plastic knife attempting to carve a small piece out without letting the dime fall. The person who makes the dime fall in has to pick it out with their teeth. (No one 3 years old or younger or with similiar ablities should play this). The dime is then washed, the flour discarded and and new flour and wax paper are added. This game can be played as long as there is interest. At our party we actually had to quit when the kids were still very into it due to time.  Last we played a sea hunt game. In this game I placed homemade scratchers tickets on my computer and put inside plastic shell-shaped boxes that I purchased at Wishing Well party store and hid them around the room. I used scratch off stickers I ordered online to cover the name of what they had one (like a lottery ticket). The children had to scratch off the circle to reveal their prize. I can't say how much they enjoyed this. They were also supposed to rescue a dolphin which were small blue dolphins I ordered from Rhode Island Novelty company. I put each child's name on the tag and there were many extras so it took them a while to find their own. The children loved this game. Before we knew it, the time ran out and the kids and their parents were asking us when the next party was.