Hands-On Activities to Crush Science Misconceptions Michael Horton Science Coordinator
Who Am I? • I am the science coordinator at the Riverside County Office of Education • Degree in physics, minor in chemistry from SDSU • Taught high school chemistry, physics, physical science, and sheltered PS for over 10 years • I have published a physics book • I have published in The Physics Teacher several times • I present regularly at CSTA, NSTA, etc. • I host the Science Misconception Podcast at http://rcoescience.notlong.com
Who Are You? What’s your name? What do you teach? How long? Where? What is a science misconception your students have that drives you crazy?
Time for a Quiz! On this sheet, there are 22 statements. Only one of them is true. Simply find that one. On your own, read them over and try to identify the one true statement. If you know the answer, don’t ruin it for anyone else.
Nobody is Immune • Everybody has misconceptions, no matter how many years they have studied or how many degrees they hold. • It’s not something to be embarrassed about. • The fewer misconceptions teachers, textbooks, and television have, the fewer students will have. Sample TV/Radio Misconception
Now a Video A Private Universe and Minds of Our Own video series about science misconceptions are available free at : http://www.learner.org
Inquiry and Misconceptions The best way to crush a misconception is to give direct experiences that contradict that misconception and then a strong explanation of how the phenomenon really works. Inquiry activities are a very powerful way to do this. Not all inquiry is “Open Inquiry.” There are generally 4 levels of inquiry, but it’s not a magic number See the free sample chapter of my book for a complete description with references. http://www.nsta.org/store/product_detail.aspx?id=10.2505/9781935155058
Levels of Inquiry Think about one activity that you do and how you could bump up the inquiry just one level.
Simple Sample • Many textbooks show the tongue maps below. • Are they true?
Simple Sample What level of inquiry was this? Could it have easily been increased to a higher level? Was this convincing? More convincing than a lecture?
Activity 1 Are hot peppers really hot? Are mints really cold? What “controls” do you need to compare your tests to? What criteria will you use for a “yes” answer?
Activity 1 What was the misconception here? What level of inquiry was this? Explanation
Activity 2 It is said that race cars have wide tires for more friction. The equation for friction: Ff = mFN does not have “surface area” in it. Does friction depend on surface area or not?
Activity 2b It is proposed that air friction slows down a car. Air resistance on a car is known to increase with the square of the car’s speed. There is no speed or square in the equation for friction. Ff = mFN Does friction depend on speed? Are cars slowed down by rubbing friction with the air?
Activity 2 What was the misconception here? What level of inquiry was this? Explanation
Activity 3 The “north pole” of a magnet is the end that points to geographical north. Build a compass to determine where Earth’s magnetic north pole is compared to the geographic North Pole. Which direction is the magnetic north pole of the Earth?
Activity 3 What was the misconception here? What level of inquiry was this? Explanation
Activity 4 Introductory Questions: Remember the first color TVs had color adjustments? Which 3 colors could you adjust? Remember the projection big screen TVs? What color were the three projectors? What colors do you refill in an inkjet cartridge? What port do you plug your computer into on the projector? What do the letters stand for? What are the 3 color schemes in Photoshop? What do the letters stand for? What 3 colors do the cones of our eye detect? What did your elementary art teacher tell you the primary colors are?
Activity 4 Big Question: What are the primary colors? Red, Yellow, Blue Red, Green, Blue Cyan, Magenta, Yellow Inquiry Question: What does a scientific color wheel look like?
Activity 4 If a color is “primary,” it cannot be made from two other colors. What do you get when you mix the following colors of light? Red and green Red and blue Green and blue Red, green, and blue Is yellow a primary color of light? What do you get when you mix the following pigments? Cyan and magenta Cyan and yellow Yellow and magenta Cyan, magenta, and yellow Is red a primary color of pigments? Is blue?
Activity 4 Based upon your answers to the previous activity: Can red, yellow, and blue possibly be the primary colors of either light or pigments? Create a color wheel based upon your findings. Your wheel should have Red, Green, Blue, Cyan, Magenta, and Yellow on it.
Activity 4 How do you make other colors in the RGB and CMY systems? How do you make orange or pink in RGB? How do you make brown or gray in CMY? Demo: What would you see if you spin a red, green, and blue snap light? Demonstration: How does an inkjet printer work?
Activity 5 Question: How far from a plane mirror (flat mirror) do you have to move away in order to see your entire body in it?
Activity 5 Draw a diagram to explain your answer. What level of inquiry was this?
Activity 6 It is said that a compound is made of elements and that the compound does not exhibit the properties of those elements. The example that is given is that iron compounds are not magnetic. Are iron compounds magnetic?
Activity 6 Info The tape itself consists of a thin plastic base material, and bonded to this base is a coating of ferric oxide powder. This oxide is a ferromagnetic material, meaning that if you expose it to a magnetic field it is permanently magnetized by the field.Inside a tape recorder there is an electromagnet that applies a magnetic flux to the oxide on the tape. The oxide permanently "remembers" the flux it sees. A tape recorder's record head is a very small, circular electromagnet. During recording, the audio signal is sent through the coil of wire to create a magnetic field in the core. Magnetic flux is what magnetizes the oxide on the tape. During playback, the motion of the tape pulls a varying magnetic field across the gap. This creates a varying magnetic field in the core and therefore a signal in the coil. This signal is amplified to drive the speakers.
Extension It is also said that an atom is the smallest division of an element that retains the properties of that element. The entire field of nanotechnology is based upon the fact that the properties of elements change drastically as they get smaller and smaller.
Activity 7 Idea: “Because the Earth’s core is mostly iron and nickel, lava rocks will be highly attracted to a magnet.” Inquiry Question: Are lava rocks magnetic? Are meteorites?
Activity 8 Thought Experiment: If Earth were the size of a basketball (9.4” height), what would be its width? Estimate an answer. Sketch a scale diagram
Activity 8 4 Volunteers: Someone use their cell phone to determine the equatorial diameter of the Earth. Someone use their cell phone to determine the polar diameter of the Earth. Someone use their cell phone to determine the percent difference between the two values. Someone use their cell phone to calculate how wide the basketball would be.
Which Earth is squashed vertically and which is squashed horizontally by .336%?
Activity 9 On the sheet of paper handed out are 10 perfect circles and one scale model of the Earth’s orbit. Can you pick out the Earth’s orbit? The squashed circle is actually squashed 100 TIMES MORE than the Earth’s orbit.
Activity 9 If time allows Come up to the hotplate and draw 15 mL of warm water into your syringe. Put your finger over the end and pull out on the plunger. What happens? How do you explain this? What level of inquiry is it?
Contact Info Email: firstname.lastname@example.org Download this PowerPoint at http://scienceinquirer.wikispaces.com/csta