Students learn that until the nineteenth century, ocean floors were considered flat, featureless plains. Early attempts to map the ocean floors used soundings taken with weighted lines from ships. This method was slow and inaccurate. In 1855, U.S. Navy lieutenant Matthew Maury published a bathymetric chart, which indicated that an underwater mountain existed in the middle […]

9th grade students learn about “The Electromagnetic Spectrum”  The electromagnetic spectrum is made up of different types of waves. Microwaves have a wavelength about the size of a housefly. Microwaves reflect off many materials, particularly metals. Radar locates distant objects using the reflective property of microwaves. You may have noticed that the glass door on […]