If your teen is interested in the inner workings of the mind and its effect on the body -- and vice versa -- point him toward a psychology experiment for his next school project or science fair entry. He'll learn more about how people think and feel while working his way toward a passing grade.
Mind Over Music
This experiment explores whether music styles affect our heart rate differently. For this experiment, your teen will need earphones, a music player, a watch, chair and a device that will accurately measure the test subject's heart rate, including a blood pressure wrist unit. She should write down the songs she'll use, including various genres such as classical, country, jazz and rock. Hook up the heart rate measuring unit, letting the subject sit comfortably in a chair for a minute before introducing music. Record the rate, which gives a baseline heart rate that any changes can be compared with. Go through the playlist, letting each song play for two minutes. At the end of two minutes, stop the music and record the heart rate. Repeat for all volunteers. In the end, she should have data on any changes in heart rate by song. She can come to her own conclusions about why certain genres had more of an effect and whether the test subject's age or musical preferences had an influence on how each responded to the music. Your teen will need plenty of volunteers for this one so you should take a turn in the chair.
Smell Versus Taste
This experiment explores whether the test subject can taste an item's flavor immediately after being exposed to a strong smell. Your teens will need strongly scented items, including oranges, bananas or perfumes, a blindfold and flavored lollypops. Each volunteer should be blindfolded. Your teen should hold the strongly scented item under the person's nose and ask the volunteer to inhale. Immediately have the volunteer stick out her tongue and place the lollypop on it just long enough for a person to get a taste. Still blindfolded, the volunteer should name the flavor of the lollypop. The experiment works best by using many volunteers of different ages and genders. Any patterns based on age or sex should be noted.
Effect of Color on Mood
Before starting this experiment, your teen should do research on the effect of color on mood and blood pressure. Based on that research, she can create a hypothesis on what she'll discover. She'll also need to create a questionnaire, based on the colors she'll be using. It should list the colors and then give multiple emotions to choose from such as tranquil, angry, sad, happy -- leave room for the participant to add his own words. Hook the volunteer up to a blood pressure monitoring unit and measure his starting blood pressure. Using differently colored light bulbs in lamps or taping different colors over a flashlight, she should proceed to show the volunteer a color, with it being the only light source in a darkened room. After three minutes of your volunteer staring at the light, measure his blood pressure. After collecting the reading, give him the questionnaire to fill out for that color. Repeat with different colors on multiple volunteers.
Drink Color and Taste
This experiment explores whether what we see influences what we taste. Your teen will need lime juice, soda water and four colors of food dye -- red, orange and purple. He should mix equal parts of soda water and lime juice together in four clear jugs and add a few drop of food coloring to each jug. Leave the last jug clear without dye and then store the juice in the fridge overnight. He should pour 20 cups of each color and have volunteers taste each cup and fill out a short survey. Make it easy for the volunteers by just having boxes to check, with the color of the drink lining the top -- red, orange, purple and clear -- and the perceived flavors listed vertically -- strawberry, lime, grape and orange. When he analyzes the results, have him look for patterns based on sex and age.