tt_icon_170For this week’s episode of Science Teaching Tips, I’ve got a story from a veteran teacher about her first year of teaching — which was quite unusual.  She was placed in a rural school in Guatemala.  You think you’ve got it tough?!  Hear about her challenges in Episode 63 – Teaching Abroad.

Two local teachers in Colorado (Jon Bergmann and Aaron Sams)  just put together a wonderful little video about how they completely transformed their high school chemistry classrooms, so that students would actually master the material.  In the video, two dynamic presenters show and talk about how they used video podcasts to make better use of lecture time by taking the non-interactive part (lecturing) out of class time and putting the stuff that kids were struggling with (homework and problem solving) into class, to improve their mastery. I didn’t think I’d want to watch a 20 minute video but I was utterly charmed by these two teachers, and their explanation of their journey along this transformation is very compelling. Their website has more on their approach to using vodcasting in the classroom.

Watch the video



Here is a long description in text of what they’re doing in case you don’t have time to watch the video (but you should watch it, you’ll get it much more, and they’re fun folks).

Peer into Jonathan Bergmann or Aaron Sams’s classes and you will see something exciting happening.  What you will observe are students taking responsibility for their own learning.  Students conduct experiments, watch video podcasts, work on assignments, interact with the class Moodle site, have one-on-one discussions with their teacher, and get tutored by their peers and cadet teachers.  This is mastery learning at work.  Students work at their own pace through science curriculum.  When they complete a unit they must demonstrate that they have learned the content by taking an exit assessment that includes both a lab and a written component.  If students score less than 85% on these exit assessments, they must go back and re-learn those concepts they missed and retake the exam.  Grades are no longer determined by a percentage but rather how much content they have mastered.

What Caused Us to Change?
We discovered software that would capture our lessons and simplify distribution over the internet.  Then we began to record our lessons and post them for students who missed class.  This was very successful in our rural school where students frequently miss class for sporting events and other school activities.  Then we realized what students really need from their teachers is not to hear us talk and “do the sage-on-the-stage thing,” but rather, to get help when they get stuck.  This prompted us to dramatically change the way we teach.  In the 2007-2008 school year we began to have students watch video podcasts at home and then use class time to do directed problem solving, more experiments, and generally get the help that they needed.  This was highly successful and the scores of students made dramatic increases.
Then it struck us.  Now that we had a library of instructional podcasts, students no longer have to all receive the same instruction on the same day.  So, in the 2008-2009 school year we implemented a mastery teaching method.  In this method students have a check-list of things to master in each unit of study.  The list includes the required video podcasts, experiments, one-on-one demonstrations with the teacher, and appropriate Chemistry problems to solve.  When students have completed ALL of the assignments and labs, they must pass the exit exam with a minimum of 85%.  If students do not score 85% or better they retake the exam as many times as needed to pass.

Implementation of Mastery
Our classrooms now resemble three-ring circuses.  Students are in various places in the content on any given day.  Lab stations around the room are set up so students can complete the experiment that is next on their check-list.  This poses some safety issues in a Chemistry class, however, with the proper training, the students have quickly adapted to this method of experimentation.  Before each lab we spend time with a much smaller group of kids and discuss the main points of the lab and safety considerations.  This makes for a more intimate learning experience for each student, giving each student far more one-on-one time with their teacher.

All Students are Successful
A huge benefit of this teaching paradigm is that ALL students are leaning.  This is the ultimate method of differentiation.  Slower students are given the extra help that they need to master the content.  Advanced students are allowed to learn on their own, which ultimately helps them to become more independent learners.

Learning Outcomes from Podcasting
In the 2006-2007 year, we gave common assessments. We agreed to use the same tests in 2007-2008 as we did in 2006-2007 and compared scores after every unit.  In addition, the math pre-requisite for chemistry was lowered from Algebra II to Geometry, thus our students came to us with lower math skills.  In addition, enrollment in the course increased by 80%.  The average scores of the students on identical science tests given before and after implementation of the podcasting model were nearly the same, showing that the podcasting model gave equivalent results with students of a lower mathematical ability.

Proof of Success with Mastery
Now, in the 2008-2009 school year, under the master model, every student is now required to master the content before progressing, and ALL students are learning.  This has been magical!  Students of all ability levels are really learning!  As much as we were excited about the 2007-2008 results, mastery learning has been an even more positive experience for our students.  Now, EVERY Chemistry student demonstrates proficiency on EVERY topic in the class, which far surpasses the level of understanding of prior student success.

Wow, I was just sent this information about a wonderful chance for teachers and students to connect (for FREE) with a really dynamic scientist, Michio Kaku.  You can see my previous post about a talk he gave on the Physics of the Impossible at AAPT last summer — he was an incredibly gifted speaker. Funny, interesting, and really tuned in to what teachers can use.

It’s next Wednesday, December 17, 2008 12:00 pm EST and hosted by Discovery Education.

Register for the event here.

Michio Kaku is a best selling author, host of two national weekly science radio programs, and frequent guest on television shows including Larry King, 60 Minutes, 20/20 and many more. He has hosted numerous programs for the Science Channel and is currently increasing people’s Science IQ every Sunday night in the series “SciQ”. If you’ve ever seen Michio speak before, you know that he has a brilliant ability to break down incredibly complex theories and explain them in ways that anybody can understand. On on December 17th, he’ll be sharing his ideas directly with you and your students! This is your chance to connect your students to one of the most dynamic scientists on the planet, and even have him address their questions directly!

Michio Kaku’s website

I’ve got so many different posts that I want to write… scribbled notes on different science myths and beautiful everyday things, but I have been so very busy. I’m sorry. I will get back to writing detailed posts in a few weeks!

In the meantime, I’d like to recycle a good old post on making your own phonograph. If you’ve got some old records, try this one, it’s pretty astounding when it works!


phonographI love this little activity… Have an old record but no record player? Here’s how you can listen to it. Take a record and stick a pencil through the hole in the middle so it’s pretty close to the point of the pencil. That’s your turntable. Now take a piece of paper and roll it up into a loose cone and tape it. Flatten the pointy end a little and stick a pin through it. You may want to tape the pin to the end of the paper cone so it’s more stable. Now have a friend turn the record by slowly rotating the pencil. Place the pin, point down, on the groove of the record, and gently hold the cone so the pin stays in the groove of the record. Try to turn it at 33 1/3 times per minute — good luck! Here is a more detailed description of the activity.

Here is my post on my podcast where you can hear how it sounds and how to teach it.

You should hear the music playing, albeit a bit wobbly. The record has a groove in it — one long spiral. The needle vibrates in response to the shape of the groove. But the needle on its own doesn’t vibrate very much air. When it’s attached to the cone, it vibrates the cone, which can then vibrate more air, making the sound louder. The cone also directs the sound, making it easier to hear.

Today’s students often haven’t seen a record before, and so it can be useful to look at it under a microscope or magnifying glass to see the groove. Note that a CD is also sort of “carved” — it has microscopic pits in it. But instead of mechanical vibrations, the grooves in the CD are so tiny that it interacts with light. That’s why records wear out — the needle wears out the grooves. That’s not a problem with CD’s, since it’s just light touching the surface. Interestingly, it doesn’t matter (as much) if you scratch the side of the CD with the rainbows on it — but if you scratch the metal coating on the other side, the light won’t reflect from it correctly and you’ll spoil the CD.

Wikipedia has more information on phonographs, and so does this site from Arbor Scientific.

If you’re interested in making your own working phonograph (not just the pin and paper method) to actually record your voice using a plastic cup (replacing the old fashioned wax cylinder), check out this kit from Make Magazine. I hear they don’t carry the kit anymore, but someone Googled and found it by a company in Japan.

Here’s a video of it in action and here’s what it sounds like.

A teacher on a teacher listserv I’m on writes:

In my collection of Edison Phonographs I have many that will allow for purely mechanical reproduction of sound. I have an Edison tinfoil phonograph that records on tinfoil (duh) and numerous machines that record on wax cylinders. First the wax cylinder is shaved to a clean surface then a cutter head consisting of a diaphragm with a sapphire cutting stylus is lowered onto the record surface. As the cylinder turns, wax is cut by the stylus where the depth of the cut represents the wave pushing/pulling on the diaphragm. It is called the “hill and dale” or vertical cut type of recording.

The Gakken phonograph made in Japan uses a side by side motion or lateral recording. This is what the common 78 RPM records used from 1896 up through the mid-1950s. The toy phonograph does work but results vary depending on numerous factors. One is the temperature of the plastic cup used for the recording. I have found that a hair dryer warming the cup helps but one must be careful not to melt anything. The Gakken machine appears on eBay regularly under the search Edison Phonograph but shipping is as expensive as the machine is because it is air mailed from Japan. Maker Shed in the US carries it as well with some savings on postage but at a higher price.

tt_icon_170Have you ever really listened to the sound of a bouncing ball? There’s some elegant mathematics to be had in this simple thing. In this episode of my Science Teaching Tips podcast, staff educator and physicist Tom Humphrey takes us to the most perfect bouncing ball I’ve ever seen (or heard) — an exhibit at the Exploratorium. The platform the ball is bouncing on is a huge chunk of heavy marble, bolted to the floor. (What does that have to do with anything? Think about conservation of energy and momentum). You hear some surprising things as a small metal ball bounces on that surface. Even without the exhibit, this is something you can do with your students, and integrate science and math into your curriculum.

Listen to the episode – Follow the bouncing ball

I just found out about a neat free service for science educators.  It’s mostly for those in Colorado, but those outside Colorado are welcome to use it as well.  It’s a free email servicer for teachers to ask questions directly of a science education expert, who will go out and find the answer for you.  How fabulous!

It’s called MAST WebConnect.

Here is some text from their site:

The Problem
Obviously the problem is not that the Internet does not contain enough math and science education resources, but finding quality resources can be an overwhelming task for teachers and students alike. Teachers often do not have the time to do a quality web search or seek experts in the field.

The Solution
MAST WebConnect will answer your questions and find high-quality web-based Internet resources personally for you! Supported by the MAST Institute and the University of Northern Colorado, WebConnect is staffed by math and science educators and professors with access to these resources and references.

How it works.
The idea is simple. We know that the Internet provides a wealth of information, but sorting through and filtering that information to find quality materials can be an overwhelming task.
That is where we come in. Contact MAST WebConnect with any mathematics or science question, and our coordinators will find the information either by contacting experts in the field, or finding high-quality Internet sites.
MAST WebConnect has a pool of available volunteer mathematics and science experts to help with more difficult inquiries. These include college professors and working scientists within Northern Colorado.

tt_icon_170Despite my better judgment, I invite TI staff educator Eric Muller to do one more set of activities on my Teaching Tips podcast —several things you can do with soda straws.  Listen to the episode – The Last Straw.

Holding Charge activity (PDF)
More of Eric Muller’s activities