Walk down any toothpaste aisle in a grocery store, and you’ll see a number of options for whitening teeth. But do they really work? With a fairly simple science project, a middle school student can find the answer, along with which toothpaste whitens the fastest and brightest. Submerge white stone tiles in bowls of coffee. After 24 hours, the tiles should have noticeable coffee stains. Using four different brands of whitening toothpaste, brush each tile after it has dried with a different toothpaste for 2 minutes and for a total of 14 brushing sessions to simulate a 2-week, twice-per-day brushing schedule. After brushing, analyze the results to determine which toothpaste works best.
Ever wondered how significant smell is to taste? With this science project, a student can find out. Using a team of blindfolded taste testers, the student will serve a variety of foods to volunteers who will sample each item twice -- once with a nose plug on and again with a fully functional sniffer. Their job is to try to identify each bite of food they sample, with the student recording all the data to determine the accuracy of tasting with and without nose plugs. Once the data is collected, the student can chart his findings and make an informed conclusion.
Middle school students interested in plants have lots of projects to choose from, but one they may find particularly interesting is how, or if, different colors of light affect plant growth. Using bean seeds, students will plant them in cups, placing the cups in boxes with holes cut on every side. Cover the holes with different colors of cellophane -- blue, yellow, red and green. Leave the cellophane off one box to see how natural unfiltered light affects the growth of the seeds. Take daily measurements of the plants’ growth for about four weeks to determine which, if any, color speeds or slows growth.
Pulling out a loaf of bread or a piece of fruit only to discover it is covered in mold is no fun, but it can lead to some interesting questions about how mold forms and if certain factors speed or slow the process. Using a variety of foods like lettuce, bread, meat, cheese and peaches, students can explore which foods develop mold the fastest, and under what conditions. Have the kids seal the different foods in plastic bags and put them in different environments -- light, dark, with and without added moisture. Check the food each day to note any mold growth, documenting the findings on each food and in each environment.