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I made ScienceFix.com to share my favorite demos that I do in my middle school science classes.  

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Media that I like...
  • Something Funny Happened on the Way to the Moon
    Something Funny Happened on the Way to the Moon
    by Sara Howard
  • NOVA - Origins
    NOVA - Origins
    starring Neil Degrasse Tyson
  • Human Body: Pushing the Limits
    Human Body: Pushing the Limits
    starring Bray Poor
Tuesday
Dec082009

Time to Pull the Plug on Teacher Tube

Teaching and video have been around for years.  Some of us remember watching films on a projector in the classroom.  Then along came video tape.  Now we are in the era of web video.  Thanks to the internet teachers have access to more video than anytime in the past.  That's in theory of course.  In many school districts the IT department locks down the network.  YouTube, Blip.tv, and other web video are blocked.  The rationale is that students would purposefully or inadvertently access inappropriate video.  Students would get into trouble for accessing it, teachers would get into trouble for inadequate supervision, schools would get bad press, so on and so on.  Hence the rise of TeacherTube.  This site was created for teachers to upload and share video for in a safe and controlled environment, away from the "anything goes" sites like YouTube.  So why am I proposing to pull the plug on TeacherTube?

I'm not really.  It serves a purpose, but it fundamentally avoids the real problem. Districts should allow teachers access to the best tools available to enrich their classrooms and streamline their  workflow.  Blocking YouTube negates that. With TeacherTube in existence, districts feel justified in blocking basically the world's video archive.  I have experienced using TeacherTube and here are the downsides:

  • Cumbersome uploading process.  Entering video information is a chore and uploading frequently fails.
  • Video quality does not match YouTube.
  • Ads inserted.  I know the site creators need to make money, but it's done in an extremely annoying way.
  • Video choice is far less.

Here are the benefits of schools having access to Youtube:

  • Easy to upload to.
  • Superior video quality.
  • Easy to search for video.
  • Huge video library.  If I need a Bill Nye clip, a Mythbusters clip, a clip of the Hindenburg burning, anything, there is a good chance that it is there.

Is YouTube perfect?  Far from it.  My biggest complaint is in embedding videos. At the end of an embedded video there are the suggested videos that are frequently inappropriate for my students (middle school students).  This needs to be dealt with. I don't embed Youtube videos on my teacher page because of this this.  I instead upload videos to Blip.tv and link to the original download source material to avoid the suggested videos. YouTube needs to offer more control of this to its users.

My district unblocked YouTube, Blip.tv and other video sharing sites about a year and half ago and what were the results?  Students did not flock to YouTube during school time because there already is a school policy in place that instructs students to use the computer for school related purposes and not for personal entertainment. Teachers frequently walk around the computer lab room and/or classroom to monitor student activity and it works.  Imagine that.  Teachers as a result have been able to infuse into their curriculum a valuable resource.  That said, why am I writing about pulling the plug on Teacher Tube?  Our district seems to be in the minority.  When I collaborate with teachers outside the district, they frequently mention that they only have access to Teacher Tube. That is a shame. Districts please trust your teachers.  They will be responsible professionals. Don't treat them like children.

Sunday
Nov292009

Video Demo: Accelerometer

Acceleration is the change in velocity over time. Velocity changes when speed, direction, or both changes. Anyone can build a simple accelerometer. The video below shows how to build an accelerometer and how to use it.

Friday
Oct302009

Video Demo: Laser Lens Eye

Teaching how the eyeball works usually involves showing diagrams of the eyeball and showing how light passes through the lens. Science teachers can also use Jello to make lenses that will show laser light refraction.  I tried that and had disastrous results.  I started to play around with mixing baby powder (mostly cornstarch) with red food coloring and water.  I was quite pleased with the results.  Go ahead and watch the video below to see what happens.

 

Wednesday
Oct142009

Video Demo: Glowing Tonic Water Fountain

The idea for this demo came from Steve Spangler Science.  In his post he states:

Tonic water might not be your first choice for a beverage, but it's the secret ingredient you'll need to make a glowing geyser. It turns out that tonic water will glow under a black light because tonic water contains quinine, a chemical that was originally added to tonic water to help fight off malaria in places like India and Africa. While the tonic water we drink today only contains a small amount of quinine, it's still enough to make your drink glow under black light. 

Instead of using mentos to make a glowing gyser, I decided to do a Hero's fountain version. You can get a simple apparatus from teachersource.com that fits into 2 2L bottles. Where in your curriculum can you fit this? In eighth grade science we cover properites of matter such as denisty, phase at room temperature, color, flame color, smell, texture, etc.  Some chemicals can be identified from the ability to fluoresce when exposed to uv light. I would maybe do this with a fountain of regular water and one with tonic water and then ask the students if the same chemical is in each founatin.

 

 

Tuesday
Aug182009

Video Demo: Sodium in Water

The alkali metals are highly reactive since they have one valence electron. One of those metals is sodium. It needs to give up one electron to become stable. When a cubic centimeter sized piece of sodium is placed into water, a vigorous chemical reaction occurs in which sodium hydroxide (NaOH) and hydrogen gas is produced. Wikipedia provides an excellent description of what happens during the reaction.

Sodium reacts exothermically with water: small pea-sized pieces will swim around the surface of the water until they are consumed by it, whereas large pieces will explode. While sodium metal reacts with water, you can observe that the sodium piece melts with the heat of the reaction to form a perfect sphere shape if the reacting sodium is small enough. The reaction with water produces very caustic sodium hydroxide and highly flammable hydrogen gas. In any case these are considered an extreme hazard and will cause severe skin and eye injury.

In the video below a small pea sized piece of sodium is placed into water. It does ignite and explode. To avoid an explosion ice water should be used. To avoid ignition a safer method can be used in which a layer of mineral oil is placed on top of the water. The mineral doesn’t react with the sodium and prevents ignition.

For a safer sodium demo, fill a large graduated cylinder with and equal portion of water and mineral oil. The mineral oil will be on top. When sodium metal is dropped into the cylinder it won’t react with the mineral oil and when it touches the surface of the water, it reacts briefly to produce hydrogen gas bubbles, thus causing it to rise back up into the mineral oil.