This past week I had the opportunity to go inside a large plastic bag and have the air sucked out. Why would I do this? I did it because this demonstration was about air pressure. When the air is sucked out of the bag, one feels the combined air pressure of 14.7 psi. It is much stronger that you would think.
Some of the students also took turns going into the bag to experience the air pressure. It was quite an interesting day in science class.
My eighth grade classes launched their water rockets last month. I took video of the students and their rockets and now have it posted to our school’s website. I made an iMovie from all the video clips. I originally had it as a twenty minute video, but I edited it down to about four minutes so it didn’t take too long to upload and play. This is my first attempt at shooting the video, editing the clips and posting to the school’s server. Check it out.
The rockets are made with two, 2-liter bottles. The top bottle is where the astronaut egg is located. The goal is to keep the astronaut safe and secure by designing an enclosure around the egg so it doesn’t crack. All types of materials are used and must be accounted for in the final cost.
The bottom bottle is the engine. We fill the bottle about half full with water and I pump it up with about 60-70 pounds of pressure. I have a specially designed rocket launcher that keeps the rocket set until I pull the pin. The students work in groups of two and this project takes about a week to complete.
It’s been quite a ride these last few months. Our son was born in July and my wife had some serious childbirth complications. It was almost August before we were all home. September was difficult with the new baby, starting school and caring for my wife. We are now just getting back to normal and getting some sleep. My new son is adorable and I thank God for a healthy family now.
I had some time to play with the Thesis theme and I just couldn’t load a header picture. A knowledge of css and programming is required to do this simple task. I have since switched over to the Headway theme and this theme is easier to work with. I hope to get back to posting about science and mathematics teaching. I think three times a week will be the goal as I have limited time and resources.
I also have some new ideas I would like to try. Being a Graduate Gemologist from the GIA, I have some jewelry that I would like to sell on Siyensya. Also, my Bisaya lessons are still ongoing and I hope to continue to the full 60 lessons. I’ve changed lots of diapers lately and I’ve have had some sleepless nights with my son, but I have a new theme that works pretty good so far and the posts will be coming.
I bought the EyeClops video microscope last week and it arrived yesterday. I took it to school and my students had it up and running in no time. I was interested to see the quality of the images and video and to see if this would be something I could use in the classroom. The first thing to do is insert 5 AA batteries. It comes with a USB flash drive that records the media. I also tried a 2 gigabyte flash drive and it worked nicely. During the day I learned to move from pictures to video and how to focus. There are three magnifications: 100x 200x, and 400x. It’s difficult to focus when using the 400x but I learned to hold it down and go from lower power to higher.
The flash drive will only hold a few megabytes of data so have another flash drive handy. Here area few pictures I took today, my first day with the EyeClops. I hope to explore more this week and have an updated post by this weekend.
Here is a piece of bread at 100x. All of these pictures were imported into iPhoto and given a quick edit using the enhance magic wand.
The second picture is an onion skin at 200x.
The third picture is the same onion skin at 100x. The fourth picture is a closeup of a pineapple at 100x. The last is a small video of a state map.
After I took these pictures, it was easy to hook the EyeClops into the VCR using the S-video and project it onto the Smartboard for the whole class to see. I bought mine for $24.99 at Amazon and it is worth the price, even if you just play around with it. We had a fun day in science class today.
Bacteria reproduce by binary fission. They break in half and one becomes two. I use this topic to link math and science when we study bacteria and viruses. I start off with the question: If you start with a penny and double it every day, how many dollars will one have in one month? Let the month have 31 days. At first, they think it might be a hundred dollars or a thousand. But I have them do the math by doubling the number 31 times and see what they come up with.
After a while,
Let there be light.
We are studying the properties of light in science class and this brings us to the study of the electromagnetic spectrum. I found a good powerpoint on this subject from Slideshare. It’s hard getting your mind around the dual properties of light: both a wave and a particle. Slideshare is a good place to find relevant science content and I go there often.
I introduce this topic from my experience of scuba diving. As one goes deeper, light is
Today, President-elect Barack Obama selected John Holdren and Jane Lubchenco as science advisers. Obama said “It’s time we once again put science at the top of our agenda and worked to restore America’s place as the world leader in science and technology.” Also joining Obama’s science team is Nobel Prize-winning scientist Harold Varmus and professor Eric Lander, a specialist in human genome research.
The class did a density lab where they change the density of water by adding different amounts of salt. The hard part is to decant the solution so the different densities don’t mix. We used food coloring to show each different density layer. The bottom layer has 2.5 teaspoons of salt. The middle layer has 1 teaspoon of salt, and the top layer has no salt, just yellow food coloring. We used 100ml of water for each layer. Put a piece of cardboard on top of the red layer to decant. The class did a great job.
Here is a good lab to check the observational skills of your students. I do this early in the year so I can check my class procedures for lab clean up. The students will also see something that is not expected, which adds to the excitement. The students will also have some practice measuring with a graduated cylinder.
To do this, measure 25 ml of half and half and pour into a perti dish. Put one or two drops of four different colors of food coloring into the half and half. Then put a match into a drop of Joy Ultra dish detergent and then put into the middle of the colors. The colors will move to the outside and then start to blend together. You can adapt this to almost any grade level.
A neat way to help students internalize a cubic centimeter is to make paper cubic centimeters, aka Groovy Cubes. All my classes made them this week and we strung them together on thread. I’ll hang them up tomorrow in the classroom. We also discussed how one cubic centimeter will hold one milliliter of pure water and the water’s mass will be one gram.
First, cut out the pattern and fold. The hard part is taping them into a cube. Get some thread and a needle and start stringing.
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