Here are some questions to get your ideas flowing:

Chemistry

  • Which metals conduct heat? 
  • How is the dissolving speed of powders (like salt) or solids (like candy) affected by heating? Type of liquid? Amount of liquid?
  • How is metal corrosion affected by liquids? Temperature? Acids like vinegar? Bases like baking soda?
  • Is there really iron in our cereal?

Physics

  • What are the differences between bulbs in series and in parallel?
  • How is electrical conductivity affected by type of material? Temperature? Type of liquid?
  • How does a sailboat work? Why are there different designs? Test performance. 
  • How does temperature affect the electricity generated by a solar cell?
  • What are the parts of an electric motor?

 

 

 Meteorology

  • How are weather instruments used in forecasting?
  • How can we create a cyclone?

 Geology

  • Which rocks are harder? Test various rocks and minerals such as quartz, granite and slate. 
  • How is coal is formed? Can we make it at home? 

 Astronomy

  • How do the planets orbit the sun?

 Anatomy and Psychology 

  • How does temperature affect people's ability to taste differences in meats? Soft drinks? Sweets?
  • Can a person detect where sound is coming from without being able to see? 
  • How is blood pressure affected by caffeine? Exercising? Bathing?
  • How do we get cavities?
  • Fingerprints -- can two people have the same one? 
 

 Botany

  • Do plants grow toward the light?
  • Are earthworms good for a garden?
  • Are bees good for plants? 
  • Why do trees have bark? 
  • Can we tell the age of trees? 
  • How is seed germination affected by amount of water?  Salt content of water? Different fertilizers? Different soils?

 Zoology

  • Do animals have the same drinking habits when given colored water? 
  • Animal prints, what information do they give us?
  • How much mass can a hungry caterpillar eat in a day? 
  • Can a snail move faster on dirt or concrete? 
  • How does temperature affect the frequency that a cricket chirps?
  • Which animal is smarter? Examples: goldfish or guppy, hamster or gerbil, cat or dog.
 

Others

  • Which brand of popcorn works best?
  • How much are fabrics damaged by sunlight? Number of washings? Type of detergent?
  • How is melting snow in sunlight affected by color?
  • Which brand of paper towels can hold the most weight? Try this experiment wet and dry.