Like so many good things that I have created in life, this post comes entirely from someone else's idea.  Dan Meyer had the first speed of light task, which I am linking for my sequel ideas, because, well, his just rock.  I wanted to include this post, because I feel like I will be able to use this version a lot easier in my grade eight class, it allows talking about cool conspiracy, moon landing stuff, Mythbusters, and is practice for me taking something that I see and turning it into something I can use in class.

Act 1 - The "Laser"

I love this set up because it is what scientists actually did!  They have reflectors on the moon at which you can shoot your lasers and receive signals back to prove that people were on the rock that is orbiting our Earth! Well, now all we need to know is how long did it take for the laser to to hit the moon and come back?

Act 2 - The Measurements

This act two is simple, I would probably use this for a started (shouldn't take too long at all), but here they are...

Act 3 - Fire the "Laser!"

Well there it is; a simple fun intro to the speed of light.


As promised, Dan has some awesome work with the same problem, which can be found here.  Check it out, you won't be disappointed.
Well here it is!  One of my best moments of stumbling onto curriculum.  I would first and foremost like to thank Delano Pauw.  He is the creator of all the media and the toppling artist; I just happened to find him on youtube.  Check out his channel.  He really is amazing, and with a quick e-mail he gave me Raw footage, dimension shots, and estimates.  All from way off in the Netherlands (this interweb thing is so cool!).

Without Further Ado, here is the domino spiral (now featuring sound).

Act 1 - The Spiral

Based on twitter results the most natural question to ask is how long will it take for all the dominoes to fall?  That is what this WCYDWT is based on.

Act 2 - Dimensions and Time Measurements

So here it is, I wanted to make students work for the dimensions a bit.  Is  this too mean?  Anyway these work well!
I will give students a printed copy of the picture from which they can gather the dimensions.  Then play the first lap of the spiral to have students get the rate of fall.  If you want to make this whole process longer give them dominoes instead of the video and have them come up with the rate of fall from experimentation.  If you are physics minded throw this in their face. I am pretty sure I don't understand a single thing in that pdf, but I haven't taken the time to go through it, but it could give some neat extensions.

Act 3 - The Reveal

Here it is, the moment we have all waited for!

Sequels and Extensions

This is the part that I find the hardest.  Where can this lesson grow legs.  Please give me a hand with making this more worthwhile, but here are some ideas that I have so far.
  • How many dominoes of each colour?
  • Graph the time of each revolution vs. its radius, find the slope (I don't actually know if this is worthwhile I haven't tried it).
  • Switch the variables around and find some bigger domino topples, ask them how many dominoes were used.
They are kind of lame, but like I said I cannot think of any.  Delano did speak about the calculations that he had to go through in creating this, maybe he can comment about that, and an extension could be that kids make their own (I am all about building these as a project).

Guiding Questions

One spot where I am a total n00b when it comes to inquiry and teaching is my question techniques.  I want to learn good leading questions that prompt students just enough to get them over hurdles.  If you guys could give me some in the comboxes that would be excellent!  Here is my start.
  • What are we trying to solve?
  • What unit will it be in?
  • What would make our final time longer or slower?
  • How can we determine how fast the dominoes are falling?
Once again, no skills here so I need your help.