May 20, 2014
by: Tami O’Connor
So, do you ever bring discrepant events into your classroom to capture your students’ attention? If so, the Poly Density Bottle should be on your list of must-haves! As you can see, this is a one-liter bottle filled with clear liquid. Floating at mid-bottle are two bands of beads, with blue on top of the white.
On its own, this is intriguing to many students. The head scratching begins, however, once the bottle is given a good shake. As soon as everything starts to settle, students will observe that the white beads now float at the top of the liquid while the blue beads sink to the bottom. The liquid, once clear, now appears to be slightly cloudy.
But wait, there’s more… After about 30 seconds something interesting begins to happen. The white beads gradually sink down, the blue beads gradually begin to float up, and the liquid above and below the beads is again clear. Now the stumper… Why is this happening? Read the rest of this entry »
May 12, 2014
Teaching with a 3D Model of the Periodic Table?
by: Roy Alexander
I never realized how easy is would be to teach with my 3D periodic table until I started listening to a science teacher at last year’s NSTA convention.
She recognized that the AAE (Alexander Arrangement of Elements) she was walking over to at my lunch table was pretty much the standard chart: rolled and folded (I knew that) and that the common 2D element arrangement is the same thing unrolled and unfolded with the familiar separations and multi-gaps. (I knew that too: it’s what I started with when fixing the gaps that annoyed me so much.)
She (Allison) said that she’d had to make her own 3D periodic table ever since her professor showed her how much better it is for introduction of the idea for middle and high school students. That’s when I began to get a glimmer of its usefulness in the classroom – beyond the motivation of novelty and appeal of the logic I used to develop it!
The photos, she told me, bring reality to the common abstract chart, and are a terrific way to have the least academic of her students to immediately identify where metallic elements are, and by seeing, for instance, the Noble Gases looking like downtown at night.
She pointed out that the Main Group element’s ability to stay as a unit all the way to the last period would make her job of teaching trends simpler – as they are most obvious that way.
(I had NO idea!)
Earlier I’d learned that although Mendeleev got only half of his missing element predictions correct, being the first to leave space for the undiscovered was pretty gutsy, giving him the right to state “…the elements if arranged according to their atomic weight…” in his Periodic Law. Read the rest of this entry »
May 9, 2014
Energy Sources in a Classroom – Scavenger Hunt
by: Roy Bentley
I had the opportunity to attend the NSTA Convention that was held last month in Boston. It was a great show with amazing displays, topics and speakers. And of course, we had the PowerWheel there demonstrating how easy it is to teach about energy.
One of the points that came up during the show that struck me as worth exploring further was when we asked the teachers we were working with was “what sources of energy do we have in the classroom” The teachers at the show answered the lights, the power outlets, the sunshine through the windows and possibly the forced air from the heating/cooling system. No one referred to the faucet. When the teachers were asked if they had ever had the electricity fail in the school they all answered yes. When asked if they had ever experienced a water failure in the school they all answered no. It was concluded that the most reliable source of energy in the room was the faucet/(gravity).
Here is a simple classroom or home activity to help students realize how many energy sources are around them all the time! Read the rest of this entry »
March 30, 2014
by: Laurie Neilsen
Is Your Amber the Real Deal?
Amber is fossilized tree resin which has undergone molecular polymerization over many millions of years. It is highly prized for use in jewelry because of its beautiful color, transparency, and lightness. It is also of great interest to the scientific community, as much of it has been found with ancient insects and plant life encased and preserved within.
Amber sales skyrocketed after the release of the movie Jurassic Park, which featured scientists resurrecting several dinosaur species by extracting DNA from mosquitoes preserved in amber, to disastrous results. Fortunately for us, scientists have recently discovered that DNA has a 521-year half-life. Dinosaur DNA would simply be too old to clone.
Unfortunately, the popularity of amber has given rise to many imposters and imitations passed off as the real thing. So how do we make sure that the amber we are purchasing is real? We have found a few tests you can do at home (or in the classroom) to verify that what you have is real fossilized amber and not plastic, glass, or copal. Copal is tree resin that has not yet fossilized. (It will, though, if you’re willing to wait a few million years.)
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March 17, 2014
by Janice VanCleave
I love the magnetic accelerator. In fact, I met friends at a restaurant yesterday and took the accelerator with me. We had a lot of fun predicting what would happen and testing our predictions. No formal steps….just making cool guesses and then discovering whether we were correct.
Yes! The steel ball shot off the end of the track and hit the floor a couple of times, but that just added to the excitement. It’s a small town and few are surprised that the eccentric science author is experimenting at the restaurant –again!
A parent came in with her daughter, a second grader. With the mother’s permission I invited the child to sit with us. The girl had sinus problems and didn’t feel well. She was a bit sluggish and her eyes looked dull, as one would expect. When I asked the child if she wanted to do some science experiments, her dull eyes brightened. She had not been present during the previous testing of the accelerator, but she was immediately interested.
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