• What substances in some rocks are radioactive?  Can radioactive materials make other materials radioactive?
  • How were X-rays discovered?


  • Does water cool off faster if it was boiled in a microwave oven vs. being boiled on top of a stove?
  • How much insulation does snow provide?  (Example: a thermometer sits in a bed of snow, with snow cover the bulb, will show a temperature of almost 32 degrees, while one outdoors with no snow cover shows about 14 degrees!)

Magnetism and Electricity

  • Make an electromagnet Model, and explain why it works.
  • Make a permanent magnet, and explain how it's done. What can make it lose it's magnetism?
  • Why does rubbing a balloon make it cling to a wall?  What other things get accidentally magnetized or "filled with static electricity" around your house?

Molecules, Ions, and Atoms

  • What properties are associated with each type of material?  hardness? Brittleness? Conductivities of electricity/cold/heat, etc?
  • What are atoms made of?  (Show at least one model - there have been 3-4 different ideas over the years, and more than one idea exists now!)
  • What is a neutron bomb?  What effects could it have?


  • What IS light?
  • Window film that blocks UV rays: How does it affect fading of fabrics?  Does it affect growth of houseplants that live behind it?  How can film keep out only certain types of light, such as ultraviolet wavelengths?
  • What is polarized light?  Why would we want to polarize light?  How do bees and other organisms use polarization of light?  How do we encounter polarized light in daily life?
  • How many colors are there in sunlight; in light from other stars/ from different types of light bulbs (i.e. incandescent, neon, CFL, sodium vapor, etc.)?  Why does a type of light source make some colors almost disappear, and others look stronger?  make a simple spectroscope to show the individual light colors in different types of light.

Black Lights/Luminescence/Fluorescence

  • What is luminescence vs. fluorescence?
  • Kinds of black lights and their uses; show how different materials fluoresce under different black lights.  (Example: Some foods, papers, rocks, and diamonds fluoresce in different colors!  Why?)
  • Make a dark box with a black light to light up a Collection of fluorescent items.

Cameras and Lenses

  • How does a camera work?  Build a Model and contrast film cameras vs. digital cameras.
  • Show how different shapes and materials bend light in different ways.  How do we use lenses?
  • How do different coatings affect lens performance?
  • Make a Pinhole Camera and explain why a pinhole can work for a simple lens.

Melting Snow

  • Different kinds of sidewalk salt: what makes them different?  How do they melt ice?
  • Why is beet juice being used on our roads to melt ice?  Are there other ice-melting methods being used?  How well do they work?