Wednesday, January 25, 2012
Visualize Radioactive Decay?
The the story that goes with the video above can be found over at Frontline. They showed the footage from an endoscope that was sent into the Fukushima reactor. It was pretty cool but the video quality degraded as they got deeper in. Watching this I remembered the Alpha particle detector I made from a webcam a couple years ago. The "snow" in the Fukushima video is likely coming from high energy particles or rays hitting the CCD of the camera.
If you have a cheap webcam and a radiation source you can easily demonstrate this. If you have an old smoke alarm you have a radioactive source. If you don't have one laying around just go out and buy a new one and swap it out for one you have at home. You're supposed to change those out periodically anyway. Additionally you can take the remaining parts of the smoke detector and use the beeper for demonstrations of the Doppler Effect.
There are full instructions for the webcam Alpha Detector over at InventGeek.com Personally, all I did when I tried this was open up a cheap webcam and put the Amaricanium source directly on the CCD. I set it up in a desk drawer so that I could close it to block out stray light.
Saturday, November 12, 2011
MDSTA 2011 - Create your own probeware. It’s easier than you think!
Below you'll find the Google Presentation I'll be using in my presentation at the annual meeting of the Metropolitan Detroit Science Teachers Association. There's not really much there, most of my presentation will be delivered via the tools I use and the website I created.
The main focus of my presentation is to investigate ways of creating sensors to use with students to collect lab data. My sensors aren't as good or as reliable as those I buy regularly from Vernier, but they often offer other advantages. Plus they are much cheaper and may be the only option a cash strapped teacher has for doing these sorts of investigations.
The main advantages to making your own sensos include:
The main focus of my presentation is to investigate ways of creating sensors to use with students to collect lab data. My sensors aren't as good or as reliable as those I buy regularly from Vernier, but they often offer other advantages. Plus they are much cheaper and may be the only option a cash strapped teacher has for doing these sorts of investigations.
The main advantages to making your own sensos include:
- Cheap - Some of my sensors can cost less that $2, the most expensive solution I've used paired a $30 accelerometer with a $20 micro-controller. That's about $300 less than the same solution using Vernier products.
- You can make sensors you can't buy from typical science education supply companies. The accelerometer I mentioned above can measure up to 250 g's! We tried to use it to find the acceleration of a bouncy ball while on the ground. We did this after calculating an acceleration of 320 g's. My students didn't believe it could be so high, so we tried to confirm it, we maxed out the sensor!
- Peer into the Black Box - Our sensors are a black box, by creating your own, and more importantly getting some students to help, we get to peek into the black box and see how they work. As we play students ask questions like, "If the accelerometer is not moving why does it read one g?"
Sunday, August 28, 2011
21st Century Learning Symposium
Before getting to my links I wanted to mention the Be Very Afraid Extra that was going on during the conference. Stephen Heppell has been running Be Very Afraid events in England for the last ten years. The original intent of these was to show how all of the money that has been spent on educational technology has paid off. Students showcase what they do and what they've learned with technology. One of the main ideas about these events is what they've done for themselves rather than what their teachers have done for them. The Be Very Afraid Extra on Thursday was the first of these to be run outside of the UK. There are already other such events scheduled for around the world later this year.
Unfortunately I didn't get to meet all the students, but I did get to meet many of them. Among my favorites were a group of middle school students who have become evangelists for Prezi. They're seeking to teach their own teachers how to use this cool tool while highlighting the advantages it has over PowerPoint. Another group consisted of an artist, a composer and a programmer, who together are creating a game for the new Windows Phone operating system. Leveraging the strengths of each to get the job done.
This sort of event highlights the possibilities technology offers our students and how those possibilities can be leveraged into learning and the beginnings of a career. The, "Be Very Afraid," is there as a message. Students often learn all of this stuff without the input of their teachers or the standard educational system. Most of the students presenting taught themselves the bulk of what they needed to know. Learning more from online forums then their teachers. Personally I think this is awesome!
Now, lets talk about me. I led two sessions. One on the creation and use of video and the other on pseudoteaching. My talk on videos and all of my links can be found at video.flosscience.com. There you will be able to find my collected wisdom on how to create videos and how to use videos to enhance what you do in the classroom.
My second presentation was on Pseudoteaching with Technology. My main goal in this talk was to get teachers thinking more about how they teach while focusing less on what tools they're using. Conferences like this one all to often focus on the "T" in "TPCK". I wanted to shift the focus more towards "PCK". You can find my presentation below. I have the feeling that my Prezi without me talking won't make much sense, but you can at least find all the links I gave out in my session. I may try to record a quick summary screen cast of the high points this afternoon. If I do, I'll post it to my blog.
Sunday, June 12, 2011
Lecture 2.0 is it a bad description or hard truth?
The press the Khan Academy has been getting has been casting a lot of light on the use of video to replace lecture. The idea is not new, it's been called likened to the Reverse Lecture or Flipped Classroom.
I've been watching things go by on Twitter and the Blogosphere for a bit. Most of which either supports the KA or points out its flaws. In the past, I've created a number of video lectures and have done some flipping myself. I also currently use video as the primary means of delivering content to my pre-engineering classes. So this debate over the use and effectiveness of video based lecture has been one I've been very interested in.
I really find myself on both sides of the fence on this one. On the one hand research (at least in physics) has shown that traditional lecture is not very effective. In Physics Education Research different strategies have grown up to make lecture better, some of which include: Peer Instruction, Just in Time Teaching, and Interactive Lecture Demonstrations. Personally, I've all but abandoned lecture in my physics classrooms in favor of the investigation heavy Modeling Physics. However, students often need extra support and they can't always make time to come in and get it. So I still make videos to support student learning.
My pre-engineering classes are about doing stuff. Mostly with electronics and programming. There are many basic skills students need before they can do the really cool stuff. I used to put up detailed instructions, either created by me or found on the web. Building my own textbook. I found most students didn't really read them. So now I deliver the same content in video form. I find more students reading the text I wrote now. Most of my students seem to feel very uncomfortable learning new skills by themselves, but the video lecture gets them started.
Now, what made me decide to sit down and write about this this morning? I was scanning my twitter feed and I ran across this exchange. It made me stop and think about it. "Lecture 2.0" is a great description of video delivered lecture. However, this label is often used as a way of denigrating the idea, but it maybe a fair name.
The original reference is to Web 2.0, so I'll start there. Web 2.0 was hailed as a way that everyone could have a voice on the internet and exchange ideas. Well, we could all do it before. I know of many websites that were basically blogs before blogging started. There were also discussion boards back in the earliest days of the internet (heck, even before the www) that allowed people to communicate and exchange ideas with people a world away. There were even free ways to create your own web pages. What "Web 2.0" did was make it easier and by making it easier drew a lot more people in. This made the experience richer and many would say substantially better. But at a fundamental level it didn't really add anything other than a new way of looking at the opportunities.
Now on to "Lecture 2.0". By feeling denigrated by this label we lend credence to the idea that lecture at it's core doesn't really help most students learn. "Lecture" has been put down for years and is often referred to with catchy names as, "Set and Get," "Sage on the Stage," or "Drill and Kill." So if lecture doesn't really help student learn, why do we still do it even in video form? I ask myself this every time I upload a new video.
So, what do we get with Lecture 2.0? The lecture is still the same for all students, however, the pacing can be individualized. I've often had students tell me they will pause the videos periodically or re-wind to catch something they missed. They can also go back to the lecture any time they want. But at the same time it is still just lecture. Some of this could happen in the classroom. Students ask for clarification or ask you to slow down. They also come in for extra help to fill in notes they missed during class. With web video this is all easier. Delivering lecture as homework gives us the opportunity to look at education differently. Just as Web 2.0 caused us to look at the internet in a new light.
By shifting lecture out of the classroom I've put it in the same role as a textbook. The interaction is one way, text to student. The student can't ask for clarification and the textbook can't check for understanding. So maybe some uses of online video in education should really be labeled "Textbook 2.0". Hey Ma, look your boy is writing a physics textbook! (I don't think she'll be able to stick it to the fridge though)
My understanding of a Flipped classroom is the one sentence description often given. "Lecture happens at home and homework is done in class!" Many professional educators see a lot of potential in this statement. However, as all simplifications, this one is a woefully inadequate description. With lecture removed from the school day teachers can now have more time for other activities, many of which go beyond simple homework. Even if it were just "doing homework" it would still more than that. The teacher can interact with individual students or small groups and have discussions to help lead them to answers. They can ask questions of students they've noticed put a wrong answer to coax the student to see their own mistakes.
My recommendation is this. If you don't really like the idea of your Flipped Classroom being labeled Lecture 2.0 then you need to throw out the one sentence descriptions. Don't try to boil down your methodology to a sentence or two. By trying to make the idea understandable to more people you end up doing the opposite. They end up filling in the gaps for themselves and they don't really do a good job of it. For years I tried to get some physics colleagues to tell me what Modeling was. They never would, I now understand they were reticent because they didn't want to over simplify the idea just to satisfy my curiosity. It wasn't until I sat through a 1-2 hour mini-workshop at a DMAPT meeting that I had an inkling of what it meant. After a three week long workshop last summer I think I have a better understanding. Ask me in a year or two and I'll hopefully have solidified my understanding, but I'm pretty sure I won't be able to describe it in a way that will have much meaning unless you give me an hour of your time.
I've been watching things go by on Twitter and the Blogosphere for a bit. Most of which either supports the KA or points out its flaws. In the past, I've created a number of video lectures and have done some flipping myself. I also currently use video as the primary means of delivering content to my pre-engineering classes. So this debate over the use and effectiveness of video based lecture has been one I've been very interested in.
I really find myself on both sides of the fence on this one. On the one hand research (at least in physics) has shown that traditional lecture is not very effective. In Physics Education Research different strategies have grown up to make lecture better, some of which include: Peer Instruction, Just in Time Teaching, and Interactive Lecture Demonstrations. Personally, I've all but abandoned lecture in my physics classrooms in favor of the investigation heavy Modeling Physics. However, students often need extra support and they can't always make time to come in and get it. So I still make videos to support student learning.
My pre-engineering classes are about doing stuff. Mostly with electronics and programming. There are many basic skills students need before they can do the really cool stuff. I used to put up detailed instructions, either created by me or found on the web. Building my own textbook. I found most students didn't really read them. So now I deliver the same content in video form. I find more students reading the text I wrote now. Most of my students seem to feel very uncomfortable learning new skills by themselves, but the video lecture gets them started.
The original reference is to Web 2.0, so I'll start there. Web 2.0 was hailed as a way that everyone could have a voice on the internet and exchange ideas. Well, we could all do it before. I know of many websites that were basically blogs before blogging started. There were also discussion boards back in the earliest days of the internet (heck, even before the www) that allowed people to communicate and exchange ideas with people a world away. There were even free ways to create your own web pages. What "Web 2.0" did was make it easier and by making it easier drew a lot more people in. This made the experience richer and many would say substantially better. But at a fundamental level it didn't really add anything other than a new way of looking at the opportunities.
Now on to "Lecture 2.0". By feeling denigrated by this label we lend credence to the idea that lecture at it's core doesn't really help most students learn. "Lecture" has been put down for years and is often referred to with catchy names as, "Set and Get," "Sage on the Stage," or "Drill and Kill." So if lecture doesn't really help student learn, why do we still do it even in video form? I ask myself this every time I upload a new video.
So, what do we get with Lecture 2.0? The lecture is still the same for all students, however, the pacing can be individualized. I've often had students tell me they will pause the videos periodically or re-wind to catch something they missed. They can also go back to the lecture any time they want. But at the same time it is still just lecture. Some of this could happen in the classroom. Students ask for clarification or ask you to slow down. They also come in for extra help to fill in notes they missed during class. With web video this is all easier. Delivering lecture as homework gives us the opportunity to look at education differently. Just as Web 2.0 caused us to look at the internet in a new light.
By shifting lecture out of the classroom I've put it in the same role as a textbook. The interaction is one way, text to student. The student can't ask for clarification and the textbook can't check for understanding. So maybe some uses of online video in education should really be labeled "Textbook 2.0". Hey Ma, look your boy is writing a physics textbook! (I don't think she'll be able to stick it to the fridge though)
My understanding of a Flipped classroom is the one sentence description often given. "Lecture happens at home and homework is done in class!" Many professional educators see a lot of potential in this statement. However, as all simplifications, this one is a woefully inadequate description. With lecture removed from the school day teachers can now have more time for other activities, many of which go beyond simple homework. Even if it were just "doing homework" it would still more than that. The teacher can interact with individual students or small groups and have discussions to help lead them to answers. They can ask questions of students they've noticed put a wrong answer to coax the student to see their own mistakes.
My recommendation is this. If you don't really like the idea of your Flipped Classroom being labeled Lecture 2.0 then you need to throw out the one sentence descriptions. Don't try to boil down your methodology to a sentence or two. By trying to make the idea understandable to more people you end up doing the opposite. They end up filling in the gaps for themselves and they don't really do a good job of it. For years I tried to get some physics colleagues to tell me what Modeling was. They never would, I now understand they were reticent because they didn't want to over simplify the idea just to satisfy my curiosity. It wasn't until I sat through a 1-2 hour mini-workshop at a DMAPT meeting that I had an inkling of what it meant. After a three week long workshop last summer I think I have a better understanding. Ask me in a year or two and I'll hopefully have solidified my understanding, but I'm pretty sure I won't be able to describe it in a way that will have much meaning unless you give me an hour of your time.
Wednesday, May 11, 2011
Open Source Probeware - Proof of Concept
I've been looking at free and cheap ways to collect lab data with computers for years now. It's finally time to merge that with my experience with Arduino that I've gained in my Electronics with Microcontrollers class. As a proof of concept I loaded Standard Firmata onto an Arduino board and wrote a Processing sketch to chart the charging and discharging of a capacitor. If I can track voltage change in a capacitor then I should be able to log data with any analog sensor.
The circuit consisted of two pushbuttons, one to charge and the other to discharge the capacitor. I used a 2200uF capacitor and two 560 ohm resistors (total 1120 ohms) for the charging and discharging circuits. The time constant (T=RC) is about 2.5 seconds.
The parts chosen were done so to ensure I had a short total charge/discharge time and partly based on what was in my tool box at the time.
Data were exported by the Processing sketch and were plotted in Microsoft Excel. The resulting graphs match predicted calculations well within the tolerances of the capacitor and resistors. Below is a short video of the Processing sketch in action and the data analysis in Excel.
So, it works. Next I need to make the graph formation more visually appealing and maybe ask for user input on the range of voltage and time limits. I also need to modify the code to export real data in seconds and voltage. After I get those things worked out, I'll play with some other senors I happen to have.
The parts chosen were done so to ensure I had a short total charge/discharge time and partly based on what was in my tool box at the time.
Data were exported by the Processing sketch and were plotted in Microsoft Excel. The resulting graphs match predicted calculations well within the tolerances of the capacitor and resistors. Below is a short video of the Processing sketch in action and the data analysis in Excel.
So, it works. Next I need to make the graph formation more visually appealing and maybe ask for user input on the range of voltage and time limits. I also need to modify the code to export real data in seconds and voltage. After I get those things worked out, I'll play with some other senors I happen to have.
Friday, April 22, 2011
Learning by Doing and Failing
I've been on break the last week, but I haven't been breaking much. There are a few projects I've been meaning to get to that I just haven't been able to. So, over the last week I've been working on a couple.
One of these relates to my never ending quest to find cheap/free equipment for collecting really good data. I don't know why I insist on spending so much time on this, as I have a full set of Vernier's stuff that I use it all the time. Probably because I work with lots of other teachers who don't have the same stuff in their schools.
Anyway, my latest foray has been on the use of an optical computer mouse as a lab sensor. I stole the idea from Glen Gilcrist (who probably stole it from T. W. Ng (2004)). My thought was to make this into a motion sensor to find the acceleration of a cart on a ramp. Then maybe write it up for the Physics Teacher. So I started with research and I turned up others who'd used a mouse as a sensor: Hernández-Walls et al 2008 and Taylor & Willson 2010. So, it looks like no one has used the optical sensor of a mouse as a motion sensor. Time to play!
Now, I'm not much of a programmer. I learned BASIC in high school and FORTRAN in college. Since then I've learned more, but it mostly relates to the Arduino microcontroller platform. So I settled on writing a mouse tracking program in Processing (which is basically JAVA) because of it's similarity with Arduino. To make an already long story short, I failed utterly. That said, I did manage to make a program that could log the position of a mouse and even "trigger" when motion was detected. However, due to the sampling rate of Processing (or my mouse?) I didn't really get enough data, plus the conversion from pixel motion to cm of mouse movement was a bit problematic.
So, why am I blogging this? Because even though I failed utterly to accomplish my goal I still learned a lot! I've been meaning to figure out how to get data out of Processing for a while, I just never sat down to do it. Now I have at least one way. I also figured out how to set up Processing to only record data when "triggered" and how to transform the output into numbers that make sense in a physics classroom. All pretty trivial to a programmer, but these were not things I'd done before.
This was a project that, while it did not bare direct fruit, still allowed me to build my knowledge. I gained a lot more comfort in Processing. Form here I was able to build a data logging volt-meter with an Arduino. I used it to log voltage from a charging or dis-charging capacitor as a proof of concept. If I can do this, I can collect data from any analog sensor! This means I should be able to create a variety of sensors for a fraction of the price of Vernier or Pasco systems. In the end they might not be as easy to use, but that is sometimes an advantage. The added benefit is that I'll be able create sensors that Vernier and Pasco don't make. I'm looking forward to getting a +/-250g accelerometer going!
Failing is important and we can learn a lot from it. Don't believe me? Just Google "Fail early, Fail Often" or read this post on failure over at QuantumProgress. Failure, or course, is not the important part. It's being willing to try something even though you know there's a chance of failure and then being able to learn from it.
We need to prepare our students to fail! We need to show them how they can learn a lot even though they did fail. It sounds trite, but we learn more from being wrong than we do from being right. This is obvious if you think about it. If you get the exact answer you were expecting you didn't really learn anything new. You have to be willing to accept that being wrong does not mean you are a bad person. It just means you don't know everything and that's OK. When you can accept this you can learn a lot from failure. If you can't accept it then you'll tend to put aside failure and lose a perfectly good learning opportunity.
References:
One of these relates to my never ending quest to find cheap/free equipment for collecting really good data. I don't know why I insist on spending so much time on this, as I have a full set of Vernier's stuff that I use it all the time. Probably because I work with lots of other teachers who don't have the same stuff in their schools.
Anyway, my latest foray has been on the use of an optical computer mouse as a lab sensor. I stole the idea from Glen Gilcrist (who probably stole it from T. W. Ng (2004)). My thought was to make this into a motion sensor to find the acceleration of a cart on a ramp. Then maybe write it up for the Physics Teacher. So I started with research and I turned up others who'd used a mouse as a sensor: Hernández-Walls et al 2008 and Taylor & Willson 2010. So, it looks like no one has used the optical sensor of a mouse as a motion sensor. Time to play!
Now, I'm not much of a programmer. I learned BASIC in high school and FORTRAN in college. Since then I've learned more, but it mostly relates to the Arduino microcontroller platform. So I settled on writing a mouse tracking program in Processing (which is basically JAVA) because of it's similarity with Arduino. To make an already long story short, I failed utterly. That said, I did manage to make a program that could log the position of a mouse and even "trigger" when motion was detected. However, due to the sampling rate of Processing (or my mouse?) I didn't really get enough data, plus the conversion from pixel motion to cm of mouse movement was a bit problematic.
So, why am I blogging this? Because even though I failed utterly to accomplish my goal I still learned a lot! I've been meaning to figure out how to get data out of Processing for a while, I just never sat down to do it. Now I have at least one way. I also figured out how to set up Processing to only record data when "triggered" and how to transform the output into numbers that make sense in a physics classroom. All pretty trivial to a programmer, but these were not things I'd done before.
This was a project that, while it did not bare direct fruit, still allowed me to build my knowledge. I gained a lot more comfort in Processing. Form here I was able to build a data logging volt-meter with an Arduino. I used it to log voltage from a charging or dis-charging capacitor as a proof of concept. If I can do this, I can collect data from any analog sensor! This means I should be able to create a variety of sensors for a fraction of the price of Vernier or Pasco systems. In the end they might not be as easy to use, but that is sometimes an advantage. The added benefit is that I'll be able create sensors that Vernier and Pasco don't make. I'm looking forward to getting a +/-250g accelerometer going!
Failing is important and we can learn a lot from it. Don't believe me? Just Google "Fail early, Fail Often" or read this post on failure over at QuantumProgress. Failure, or course, is not the important part. It's being willing to try something even though you know there's a chance of failure and then being able to learn from it.
We need to prepare our students to fail! We need to show them how they can learn a lot even though they did fail. It sounds trite, but we learn more from being wrong than we do from being right. This is obvious if you think about it. If you get the exact answer you were expecting you didn't really learn anything new. You have to be willing to accept that being wrong does not mean you are a bad person. It just means you don't know everything and that's OK. When you can accept this you can learn a lot from failure. If you can't accept it then you'll tend to put aside failure and lose a perfectly good learning opportunity.
References:
- Taylor, R and W. Willson, 2010, Using the Scroll Wheel on a Wireless Mouse as a Motion Sensor, Phys. Teach. 48, 608.
- R Hernández-Walls et al 2008, Design and calibration of an inexpensive digital anemometer, Phys. Educ. 43, 593.
- Ng, T.W., 2004, Measuring Viscoelastic Deformation with an Optical Mouse, J. Chem. Educ., 81 (11).
Sunday, April 10, 2011
Free research papers you can read on your iPhone or iPad
I really need to stop checking Twitter when I have work to do! I sat down this morning with my coffee to grade some papers. But I thought I'd check my email and such first. More than two hours later and I still haven't started grading those quizzes yet. I saw a tweet by @lookang re-tweeted by @fnoschese and then I fell into a time sink.
The subject of the tweet was the IOPscience Express App for iPad, iPhone, or iPod Touch. The app gives you access to IOP's extensive database of journals. Normally you can buy copies of articles from the database for something like $30 ea. However, with the iOS app you can download 20 articles for free every month!
The only gripe I have is that the articles can only be read in the IOP app. Many iOS apps will allow you to open documents in other programs. I'd really like to be able to pull these articles into GoodReader so I could highlight and annotate them. The other problem with this is if they ever update the app you'll loose all the articles you've downloaded. But it's free and the article downloads are free, so I can't complain too much.
I've been spending my morning reading articles from Physics Education. The articles remind me a lot of AAPT's Physics Teacher. There's some really good stuff here!
The subject of the tweet was the IOPscience Express App for iPad, iPhone, or iPod Touch. The app gives you access to IOP's extensive database of journals. Normally you can buy copies of articles from the database for something like $30 ea. However, with the iOS app you can download 20 articles for free every month!
The only gripe I have is that the articles can only be read in the IOP app. Many iOS apps will allow you to open documents in other programs. I'd really like to be able to pull these articles into GoodReader so I could highlight and annotate them. The other problem with this is if they ever update the app you'll loose all the articles you've downloaded. But it's free and the article downloads are free, so I can't complain too much.
I've been spending my morning reading articles from Physics Education. The articles remind me a lot of AAPT's Physics Teacher. There's some really good stuff here!
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