Ask HN: Recommend science experiments and videos for unfortunate school students
24 comments
I can think of two wicked experiments right now. I don't know if they're relevant to you, but I'll describe them and you can decide for yourself.
1. You tie a string from the wall to a motor. Ideally you should be able to control the frequency of the motor, but if you don't have this equipment, it's okay. The string will vibrate rapidly. You then close the lights and put a stroboscope on the string. You tune it, by trial and error, to the same frequency of the motor. Then you see the string frozen in a wave form. You can change the freq slightly to make it move slowly. You can have the kids touch the string at the proper places to make standing waves.
2. This one is really simple to do. You take a small object (like a soda can) and tie it with a string to the ceiling. (Let's say the string's length is about half the height of the ceiling.) You pull back the can and release it, making it swing from left to right (Without a circular swing.) Then you hand out "half-sunglasses" to the kids. It could just be a piece of dark film, or a partly opaque glass. As long as it's a bit dark and you can see through it. You put the film on one eye, you see the can going in a circle. You put it on the other eye, you see it going in a circle the opposite direction.
This happens because the eye with the dark film gets a lower refresh rate. The image on that eye is of the can in a slightly retarded position than the other eye. This messes with the 3D analysis that the brain does, and makes it look like the can is getting closer/farther from you.
1. You tie a string from the wall to a motor. Ideally you should be able to control the frequency of the motor, but if you don't have this equipment, it's okay. The string will vibrate rapidly. You then close the lights and put a stroboscope on the string. You tune it, by trial and error, to the same frequency of the motor. Then you see the string frozen in a wave form. You can change the freq slightly to make it move slowly. You can have the kids touch the string at the proper places to make standing waves.
2. This one is really simple to do. You take a small object (like a soda can) and tie it with a string to the ceiling. (Let's say the string's length is about half the height of the ceiling.) You pull back the can and release it, making it swing from left to right (Without a circular swing.) Then you hand out "half-sunglasses" to the kids. It could just be a piece of dark film, or a partly opaque glass. As long as it's a bit dark and you can see through it. You put the film on one eye, you see the can going in a circle. You put it on the other eye, you see it going in a circle the opposite direction.
This happens because the eye with the dark film gets a lower refresh rate. The image on that eye is of the can in a slightly retarded position than the other eye. This messes with the 3D analysis that the brain does, and makes it look like the can is getting closer/farther from you.
Your second experiment is absolutely fantastic, and I have used it. I was disappointed to find that the kids actually seemed to learn nothing from it. The principles seem to be pretty deep, and there's actually a lot going on. Maybe I didn't explore it enough, but I think it's a difficult experiment to "get" until you're older.
Your first one is easiest done with a "slinky". You don't need a strobe, because it all happens really, really slowly.
Off-topic: Some people are like slinkies. Of no real use, but they still make you laugh when you see them tumble down stairs ...
Your first one is easiest done with a "slinky". You don't need a strobe, because it all happens really, really slowly.
Off-topic: Some people are like slinkies. Of no real use, but they still make you laugh when you see them tumble down stairs ...
I'm in a similar position, but I'm in a Tibetan refugee camp. The children and teenagers here already get (limited but sufficient) food and shelter, so it's a good place for potential teaching.
Got an email address? Also, it'd be nice of you to tell us how it went afterwards.
Got an email address? Also, it'd be nice of you to tell us how it went afterwards.
As a high school physics student, the experiments that I feel would be most educational/enlightening are:
- Measuring gravity using a pendulum (using T=2.pi.sqrt(l/g))
- Measuring the resistivity of wire
- Measuring values for specific latent heats, specific heats of fusion etc
When doing experiments, I always found the ones where we were trying to calculate a known value experimentally (g, specific heats etc) to be the best.
When doing experiments, I always found the ones where we were trying to calculate a known value experimentally (g, specific heats etc) to be the best.
I don't have much more to add to the other comments. I just wanted to say THANK YOU for doing this.
You can do a lot for 2) with Slinkys or other long springs and a stopwatch to help understand waves, frequency, etc.
There's also a cool outdoor experiment you can do to measure the speed of sound by clapping pieces of wood/books together in a constant, even rhythm such that you hear an echo between each clap (so you hear clap - echo - clap - echo). By measuring the distance to the wall, and timing the sequence for a set number of claps/echoes, you can get a good estimate of the speed of sound. You can also make a game to see which "team" can get the best measurement. It's a very cheap demo, but it utilizes a lot of concepts of physics and physics experiments.
There's also a cool outdoor experiment you can do to measure the speed of sound by clapping pieces of wood/books together in a constant, even rhythm such that you hear an echo between each clap (so you hear clap - echo - clap - echo). By measuring the distance to the wall, and timing the sequence for a set number of claps/echoes, you can get a good estimate of the speed of sound. You can also make a game to see which "team" can get the best measurement. It's a very cheap demo, but it utilizes a lot of concepts of physics and physics experiments.
I always loved this guy, julius sumner mills. I still love him and his enthusiasm for physics. I would definitely check out his experiments.
http://www.youtube.com/watch?v=KCcZyW-6-5o
Here's his one on heat energy: http://www.youtube.com/watch?v=jhQEVR_Tsiw&feature=relat...
Also, physics for future presidents is a cool video lecture series at berkely. The first lecture is on heat: http://www.youtube.com/watch?v=6ysbZ_j2xi0
http://www.youtube.com/watch?v=KCcZyW-6-5o
Here's his one on heat energy: http://www.youtube.com/watch?v=jhQEVR_Tsiw&feature=relat...
Also, physics for future presidents is a cool video lecture series at berkely. The first lecture is on heat: http://www.youtube.com/watch?v=6ysbZ_j2xi0
I'm not quite sure what you would want to do for experiments, but Walter Lewin has a pretty good set of introductory physics video lectures on Open Course Ware. He's somewhat famous for his physics demonstrations.
MIT link: http://ocw.mit.edu/OcwWeb/Physics/8-02Electricity-and-Magnet...
Youtube Link for promo: http://www.youtube.com/watch?v=7Zc9Nuoe2Ow
MIT link: http://ocw.mit.edu/OcwWeb/Physics/8-02Electricity-and-Magnet...
Youtube Link for promo: http://www.youtube.com/watch?v=7Zc9Nuoe2Ow
Get them to play with toys that demonstrate scientific principles. It's amazing how much they absorb. Then you will have a solid basis from which to say "How does this work? What do these have in common?"
I found this link some time ago here on HN:
http://www.arvindguptatoys.com/toys.html
Pick two or three, make the toys, play, then ask "What did you see?" and "Why is it so?"
I don't know your experience in teaching, but your willingness and enthusiasm are fantastic.
Good Luck!
I found this link some time ago here on HN:
http://www.arvindguptatoys.com/toys.html
Pick two or three, make the toys, play, then ask "What did you see?" and "Why is it so?"
I don't know your experience in teaching, but your willingness and enthusiasm are fantastic.
Good Luck!
Thats an awesome link! Exactly the kind of thing I was looking for.
I don't know about India but in the states you can get model rockets or those pop-bottle water rocket kits. Maybe some creative rigging with a postage scale to measure forces and demonstrate the equal/opposite reaction of throwing matter (water) out the back of the rocket at high speed?
Electromagnetic stuff: here's instructions on making a motor out of some wire, a magnet and a double-A battery. http://www.ehow.com/how_4422383_make-battery-motor.html
Other thoughts would be to check out instructibles.com, it's not geared towards science but a lot of the projects outlined could easily be used to demonstrate principles.
Electromagnetic stuff: here's instructions on making a motor out of some wire, a magnet and a double-A battery. http://www.ehow.com/how_4422383_make-battery-motor.html
Other thoughts would be to check out instructibles.com, it's not geared towards science but a lot of the projects outlined could easily be used to demonstrate principles.
Awesome initiative. If I had to teach physics on a shoestring budget I'd go back in time to the 1700's or so, take the methods and principles as discovered then and teach science as a method instead of physics specifically.
Use physics as an illustration of what goes in to good science with the relatively simple devices of that age and you're laying the foundation for more education later on.
For example, your '4', heat: I'd use a simplified Stirling engine for that, it wouldn't take more than a bunch of clothes hangers and tin cans to make a working heat engine, which gives you all the hooks you need to go from Boyle to Carnot.
Use physics as an illustration of what goes in to good science with the relatively simple devices of that age and you're laying the foundation for more education later on.
For example, your '4', heat: I'd use a simplified Stirling engine for that, it wouldn't take more than a bunch of clothes hangers and tin cans to make a working heat engine, which gives you all the hooks you need to go from Boyle to Carnot.
The Exploratorium Cookbooks are expensive, but full of lots of great ideas:
http://store.exploratorium.edu/browse.cfm/4,19.html
The Exploratorium Snackbooks are also very good.
The Exploratorium Quarterly magazine was also great. Although it is not published any more, I see that you can buy copies at abebooks. You should search for anything with Exploratorium in the title. It is probably worth buying.
The Exploratorium Snackbooks are also very good.
The Exploratorium Quarterly magazine was also great. Although it is not published any more, I see that you can buy copies at abebooks. You should search for anything with Exploratorium in the title. It is probably worth buying.
Google give some good results for "interactive physics" http://www.google.com/search?hl=en&q=interactive+physics
For example:
http://serendip.brynmawr.edu/sci_edu/physites.html
For example:
http://serendip.brynmawr.edu/sci_edu/physites.html
Youtube has some really interesting material, let me know if you want me to make a course for 5) The Universe.
What kinds of computer concepts will you be teaching to the kids (Word/Excel, basic programming, data structures and algorithms)? Do they have access to any computers outside of class, like in an Internet cafe, or even on a cell phone that can be hacked to accept code?
I was thinking I will need to teach:
1) Importance and applications of computers 2) How it might be affecting the life of these kids without their own knowledge 3) How computers work in a very simplified way 4) Using computers for fun
A charity organization has donated about 6 computers which they have kept in a room. I guess the students will have access to these.
1) Importance and applications of computers 2) How it might be affecting the life of these kids without their own knowledge 3) How computers work in a very simplified way 4) Using computers for fun
A charity organization has donated about 6 computers which they have kept in a room. I guess the students will have access to these.
Just a thought in addition to the physics lectures (which are definitely important) - programming, or maybe even simple data entry, is probably the easiest way to earn money during spare time while still gaining knowledge and experience. If these kids could learn how to program and had access to computers with Internet access, I think there could be a way for them to earn some money and gain early job experience. And if the programming/computer lessons are related to physics, you could teach both at the same time.
I know some people would find this controversial since this is a high school classroom and not a vocational/trade school - that the kids need to focus on learning and building a strong educational foundation. But I'm from India and know how bad the situation can get... these kids are probably under a lot of pressure to earn for their families. Besides, I'm guessing there are people in the US with PhDs that are struggling to find jobs in this economy... if one benefit of a strong, pure educational foundation is some guarantee of job security in the future, it certainly isn't always the case.
Can anyone think of realistic ways that kids in this situation could make money by coding, or doing something computer related, on the Web? Amazon Mechanical Turk comes to mind, but I don't know much about it, or if the tasks involved will teach you anything significant.
I know some people would find this controversial since this is a high school classroom and not a vocational/trade school - that the kids need to focus on learning and building a strong educational foundation. But I'm from India and know how bad the situation can get... these kids are probably under a lot of pressure to earn for their families. Besides, I'm guessing there are people in the US with PhDs that are struggling to find jobs in this economy... if one benefit of a strong, pure educational foundation is some guarantee of job security in the future, it certainly isn't always the case.
Can anyone think of realistic ways that kids in this situation could make money by coding, or doing something computer related, on the Web? Amazon Mechanical Turk comes to mind, but I don't know much about it, or if the tasks involved will teach you anything significant.
Teaching kids about computers is great, but given your limited time, and the limited availability of kit, my personal feeling is that you'd be best spending most of your time teaching them basic science. Having a good grasp of doing experiments, measuring things, and general problem solving, is of great value in everything they may end up doing. Teaching them "about computers" pretty much only teaches them about computers.
In the end, though, it is your judgement. You have to teach them
a) what you're comfortable with
b) what they will respond to
c) what seems to provide value, short and long term.
I think basic science is better than "about computers", but you'll be the man on the spot, and it will be your call. I think you're doing a fantastic thing.
In the end, though, it is your judgement. You have to teach them
a) what you're comfortable with
b) what they will respond to
c) what seems to provide value, short and long term.
I think basic science is better than "about computers", but you'll be the man on the spot, and it will be your call. I think you're doing a fantastic thing.
Which area of India does this school belong to? Your initiative looks interesting
Bangalore. The state of govt. schools is pretty much the same in most parts of the country. You could always lend a helping hand irrespective of where you are. You could try approaching the school head master directly or you could go to the local rotary club and check if you can assist them in an way.
Saturday morning science, experiments on the ISS
http://spaceflight.nasa.gov/station/crew/exp6/spacechronicle...
http://spaceflight.nasa.gov/station/crew/exp6/spacechronicle...
Good education in India at school level is mostly provided by private institutions which are generally expensive. Only kids from very poor families study in government schools. The reason is: Education is free till the age of 14 in these schools. So parents don’t have to pay any fee. Most kids studying here are laborers and beggars (both are illegal but kids don’t have any other way to survive). Lot of relief organizations have taken intiatives to get such children into government schools to improve their quality of life. The motivation for these kids to attend school is that they get free lunch, a roof over their head for a few hours each day, have fun with other kids and also escape from the harsh realities of their difficult life.
I studied in a good private school but only remember complaining about it when I was there. But after visiting the govt. school, I think I studied in heaven. I was told that the teaching staff hasn't been paid a salary for the past few months. The staff themselves are not very too great in terms of quality of knowledge but I appreciate them doing their best for these kids when they aren't being paid. They even take turns to come on weekends to take special classes for the kids.
I paid a visit to the school this morning and was shocked to see the facilities. The class I am to teach is a small 15ft by 15ft room cramped with 35 kids. Surprisingly, they managed to fit in benches and chairs for these kids. There is no table for the teacher. I was hoping to be able to do some practical experiements in the class to make the kids understand better (They do not have any labs and everything they learn is purely theoretical and driven from an exam point of view to score marks that will help them move to the next class). I was happy to see an electrical plug point to connect a laptop. I think I might able to arrange for some space to perform some experiments outside the class on the corridor.
Now, I need to figure out what experiments to perform and what videos to show these kids to help them understand physics better. I also need to figure out how to introduce computers to them in layman language.
This won't be an easy task for two reasons:
1) I am not fluent with the local language. Even though the medium of instruction is English, knowing the local language would have helped. For this reason, it is very important that the experiments teach the kids more than my language. Choosing the right experiments is very important.
2) Computer related explanations should be able to connect to these kids daily lives. This will need some good thinking.
I need HN to help me by suggesting simple experiments and the angle from which I could teach these kids the benefits of using computers and also what would be appropriate to teach. I was thinking I will visit a toy store today and look for ready-to-buy Physics and Electromagnetic Kits. However, I am not sure if I will find something good. If not, I need to come up with experiments on my own.
Chapters to be explained in physics by experiments and/or videos:
1) Electromagnetic Induction: Basics of induction, Fleming's and Faraday's rules/laws, AC/DC Dynamo, Motors (Mostly experiments and videos only if absolutely essential) 2) Electromagnetic Radiation: Electromagnetic spectrum, wavelength, frequency, photoelectric effect, LASER (Mostly experiments and videos only if absolutely essential) 3) Rockets and artificial satellites: Principles involved, basics of propellants, orbital and escape velocities, types of satellites, indian space programs (Mostly videos and few experiments) 4) Heat : Latent heat, engines and their functioning (Mostly experiments and videos only if absolutely essential) 5) The Universe: Sun, Stars, Milky Way, Galaxies, Evolution of Stars and Origin of the universe (Only videos)
I have about 2 hours on Saturday to do the physics and about the same time on Sunday. If I do not finish I intend to go to the weekend after and keep doing so until I finish. If I like the experience, I intend to keep doing this on a regular basis.
Thanks in advance for any suggestions.