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Choose a Science Fair Project Idea

A key step in the Science Fair process is to choose a science fair project idea. Jump start the idea flow by having young scientists consider what interests them—and this is the really important part—in the form of a testable question.

In Getting Started, an explanation of a “testable question” was given. You may wish to review that section in order to help students narrow the focus of their investigation.

A good testable question sets up the investigation. Then it’s time to choose the details. The table below shows how testable questions could be addressed in an investigation. Any of the variables could be chosen as the changed or “independent” variable.

NOTE: It is not essential at elementary level to use the terms “independent, controlled, and dependent” variables. Students can use the questions, “What is changed?” “What Stays the Same?” and “Data Collected” to design and conduct investigations.

Elementary Science Fair Project Ideas (Easy)
Testable Question What is changed? What stays the same? Data collected
What amount of water is best to grow tomatoes?   Amount of water (.5L, 1L, 2L) Soil, amount of light, type of plant, temperature, location Height of each plant over time
What type of paper makes the best paper airplane? Type of paper Design of plane, size of paper, thrust, air currents Distance plane travels using the same amount of thrust
Does the sun heat salt water and fresh water at the same rate? Salinity of the water (grams of salt per liter) Container, starting temperature Temperature over time (1 hour)
What is the best insulator to keep ice from melting? Type of insulation in a container Amount of ice, starting temperature Time for ice to completely melt
Middle School / High School Science Fair Project Ideas (Complex)
Middle School Level Testable Questions What is changed? (Independent Variable) What stays the same? (Controlled Variables) Data collected (Dependent Variables)
Which combination of lubricants will work best on a wheel?* Individual lubricants and combinations of lubricants Wheel size, axel type, thrust to start the wheel, Distance wheel will spin for each combination of lubricants
Which detergent removes stains the best? Type of detergent, type of stain Type of cloth, physical process of stain removal Stain fading over time for combinations of detergents and stains
What conditions keep bread mold from growing on bread? Conditions of containment, temperature, moisture Bread mold, type of bread, Spread of bread mold over time
What type of food and feeder will attract the most cardinals? Bird food and feeder type Location, time of year, Number of cardinals attending each type of bird feeder with different foods

* this investigation was originally developed by William Garrett Pete, Discovery Young Scientist Challenge 2006 Award Winner