For this experiment, the student should choose a number of different carpet cleaners. This can be as little as two different carpet cleaners, but four or five may be better. Using more than two carpet cleaners will allow the student to have plenty of information to write about in their lab report. The student will also need to choose substances for the stains. These should be items that are known to cause stains, such as grape juice, grass, peanut butter, ink or spaghetti sauce. The student will need the same number of carpet squares or samples as they have carpet cleaners. Carpet squares and samples can be obtained inexpensively or even free from carpeting stores. The student should ask the manager if they have any carpet scraps or discontinued carpet samples.
The student will stain each carpet square with each of the staining substances. Be sure to label each stain, so it can be identified after the carpet cleaner has been applied. Once the stains are set in, take a picture of each square to use as evidence in the final lab report. The student will then use a different carpet cleaner on each carpet square, closely following the instructions on the carpet cleaner. For example, if you have three different carpet cleaners, than you should also have three carpet squares, and each carpet square should have a stain from each of the staining substances.
Once the stain remover has been used properly, new pictures should be taken of the carpet squares, and the student should write a detailed report on which carpet stain removers removed which stains the best. Keep the carpet squares to include in the science fair demonstration, as well as the before and after pictures.
Choose multiple candles made from different materials and having different levels of hardness. For example, the student may choose a typical wax candle, a soy wax candle and a beeswax candle. For this type of experiment, it is probably best to use taper candles since they burn evenly and easily.
Measure the candles prior to lighting them. Measuring the burning can be done in one of two ways. The student can set a timer for a predetermined amount of time, like two minutes. Then light the candles and start the timer. In two minutes when the timer goes off, blow out the candles, and measure their new height. The other way this could be done is to mark a measurement on the candle, like two inches down from the wick. Then light the candles and start a stop watch to see which candle burns down to the two-inch mark first.
Either way the experiment is performed, the student can then compare the differences in the burning time with the hardness of the wax.
For this experiment, the students will need to get planters, a strong magnet and radish seeds. Radishes grow quickly from seeds, which makes them ideal for this experiment. In the first planter, simply plant the radish seeds and give them plenty of light and water to grow. This planter will be the control radish. In the second planter, plant the radish seeds on one side, and bury the magnet on the other side. Then provide this plant plenty of water and sunlight to grow.
The radishes are ready when the red tops come up through the surface of the dirt and are visible. At that time, pull the radish up and then compare the differences in the radishes. As long as the experiment is done close to the science fair, the radishes should be saved and included in the presentation. Otherwise, pictures should be taken to demonstrate any differences in the radishes.
For this experiment, you will need two pots, water, a measuring cup and table salt. Fill each pot with the exact same amount of water. In one pot, you will have just water; this will be your control. In the second pot, you will add a tablespoon of salt to the water; this will be your experimental one. Put each pot on a different burner, and then turn the burners on to the exact same temperature. Leave the pots uncovered.
Set a timer, so you have an exact time of when the water started to boil. Stand by the stove and record visual differences while you wait for the water to boil. For example, does one start to bubble first? Does one go from bubbling to boiling faster?
Carefully record the differences.