Compare the sounds produced by a symphony with those produced by a high school orchestra, the notes produced by hitting a tympani with those produced by hitting a trash can lid, and the sounds produced by Al Green with those produced by Yoko Ono. Even though the pitch of a note (determined by the "frequency" of the sound wave) is the…

In this article, Bill Robinson describes the three main classifications of gait for animals: (1) Plantigrade--animals that walk on their entire foot; (2) Digitigrade--animals that walk on their "toes"; and (3) Unguligrade--animals that walk on the tips of their toes or hooves. Robinson explains each gait in great detail, but leaves his…

Defining friction and asking what causes it might seem like a trivial question. Friction seems simple enough to understand. Friction is a force between surfaces that pushes against things that are moving or tending to move, and the rougher the surfaces, the greater the friction. Bill Robertson answers this by saying, "Well, not exactly".…

A convenient place to begin discussing overall wind patterns on Earth is to explain coastal winds. If you live near the coast (that would be near an ocean) or even near a large lake, you probably know the general pattern of winds there. During the day, breezes tend to blow from the water in toward the land, and at night, this tends to reverse,…

How is calculus used in science? That might seem like an odd question to answer in a magazine intended primarily for elementary school teachers. After all, how much calculus gets used in elementary science? Here the author guesses that quite a few readers of this column do not know a whole lot about calculus and have not taken a course in…

The question examined in this "Science 101" column was inspired by "Find Your School's Analemma" (in this issue). What causes the Sun's apparent position in the sky to trace a figure-eight pattern throughout one year? The analemma, or figure eight pattern that the Sun makes throughout the year, is due to two major…

At first glance it seems easy to attribute cause and effect when it's not applicable, either through mistakenly taking every correlation as a cause and effect relationship, misinterpreting the meaning of independent and dependent variables, or not focusing on direct causes. Sometimes it's easy to help students understand where…

Electromagnetic induction is the technical name for the fact that, when a wire is moved near a magnet or a magnet is moved near a wire, an electric current flows in the wire. Although Bill Robertson honestly admits to not knowing why this happens, he does say that it is possible to get a deeper understanding of what's going on in terms of…

Bill Robertson thinks that questioning the physics behind simple machines is a great idea because when he encounters the subject of simple machines in textbooks, activities, and classrooms, he seldom encounters, a scientific explanation of how they work. Instead, what one often sees is a discussion of load, effort, fulcrum, actual mechanical…

Contrary to popular opinion, electron microscopes are not used to look at electrons. They are used to look for structure in things that are too small to observe with an optical microscope, or to obtain images that are magnified much more than is obtainable with an optical microscope. To understand how electron microscopes work, it will help to go…

Figuring out the difference between liquids and solids seems like a silly question at first. After all, don't we know that liquids do not have a definite shape and therefore assume the shape of their container? Place a drop of water in a short glass. Does this water take the shape of the glass? Nope. It just sits there on the bottom of the…

This article explains why spiders don't stick to their webs. Spiders don't get stuck in their own webs (and they aren't immune to their own glue) because they use a combination of sticky and nonsticky threads (different glands for producing those), and the glue is in droplets that the spider can avoid but the prey can't. The spider's nervous…

Often the writing that students in elementary school do in connection with science is their final report of a science fair project. They diligently file a report in the form of the scientific method--introduction, hypothesis, materials, procedure, results, and conclusion. This form of science writing persists through college courses in science,…

Scientific explanations often make use of things that cannot be seen or felt, such as protons, electrons, and quarks. Do these things really exist? If so, how do is it known that they exist? Imagine being enclosed in a completely dark room with no light at all and not being able to see a thing. Being chained to a chair somewhere in the room, and…