My son chose to have a science party for his 7th birthday. I hand made his party invitations to look like beakers with green stuff oozing out the top. The invitation read "you are invited to oooze on over...", you then pulled up on the green ooze, and found the details of the party written inside. We placed several bowls of gumdrops and toothpicks on a large table, and as the guests arrived, they made "geodesic gumdrop sculptures", by connecting gumdrops together with toothpicks into whatever form they chose.  It kept them busy while we waited for everyone to get there. We labeled the structures with the child's name and put them in a large green gift bag for them to take home later.  We then made slime using a glue/borax solution, and packaged each child's slime in a ziploc bag to take home.  Some of the kids didn't like touching the slime, so we had latex gloves on hand for those kids who wanted them.  We then turned all the kids into "mad scientists", by feeding them each a spoonful of "magic powder" which would foam up when mixed with the saliva in their mouths.  The mixture was citric acid, baking soda, powdered sugar, and green kool-aid powder. The kids got a kick out of watching each other spew green foam out of their mouths. We also packaged up a small amount of the foaming powder to put in each child's take home bag. After that, we brought out a big bowl of cornstarch and water mixed together.  We demonstrated that you can roll the mixture into a ball, and it will feel firm, but when you let it rest in your hand, it will "melt". The kids had a great time letting the mixture ooze out of their hands and onto the floor or table. We packaged up a sample of this mixture and put it in the take home bags.  We then made alkaselzer rockets with clear film canisters, and let the kids launch their rockets off a few times each.  Again, we put the film canister along with a package of alkaselzer in each child's take home bag.  We then tested each child's sense of taste by placing a lifesaver on their tongue (with their eyes closed). They had to try to guess the flavor of the lifesaver.  Most of them couldn't guess the flavor, but they realized that their senses all sometimes need each other to work efficiently. We put a small bag of lifesavers in each goodie bag to take home.  Lastly, we tested their sense of touch by filling balloons each with a different substance.  Blue balloons were filled with flour, green balloons with salt, and black balloons with rice.  We gave all the kids one of each kind of balloon, and they had to guess what was in each of the balloons.  They had fun afterwards, squishing the balls into different shapes. They got to take home the squishy balls in their bags as well. We then served cupcakes that I iced with green food coloring and decorated with sour gummy worms.  For the last activity of the day, we laid out several different kinds of ice cream syrups, toppings, sprinkles and whipcream. We gave each child a scoop of vanilla ice cream and let them make their own ice cream creations to eat.  We then sent them home with their goodie bags full of stuff they had made or did while at the party.  It was a lot of fun!!!