Swinging Balls

[Note to self: always preview a movie before showing it to your class, even if it's a movie supplied on the Discovery Education web site designed for children.]

So we all know that the last few weeks of school are filled with, well, time-killers. I really made an effort though to use that time to finish up some last minute science lessons.
You know… actual teaching.
Our district subscribes to Discovery Education's web site that has streaming videos on about every topic imaginable. I use it all the time because most of the videos are very well done and you can use whole videos or simply show applicable video segments.
So I was teaching about magnetism and energy during those last weeks of school and at the last minute I found a video on Discovery that looked very topical for our learning that day…
And it WAS all about energy…
And magnetism…
And, as a bonus I suppose, it had a more than a few opportunities to teach students about such things in ways that, when viewed through the overtly dirty minds of some of my fourth graders, appeared a bit racy.
Take the "swinging balls" experiment for example.

I believe the actual name for this thing is Newton's Cradle or Newton's Swing.


All I know is that all through this section of the video, the narrator kept saying things like:
"What do you think will happen if I lift one of my balls and then let it go?"
"Will all of my BALLS swing wildly?"
"Will none of my BALLS swing at all?"
"What if I lift up two of my BALLS?"
"How can I make all of my BALLS swing?"
I watched as the eyes of my boys darted around the room at each other, and little smirks grew on their faces. Then the soft giggles began and I admonished them for not behaving like scientists.
The giggles then became stifled snorts and hidden snickers….
from me.
Gimme a break! The dude kept saying "swinging balls!"

After the "Swinging Balls" experiment, the video went on describe how energy can be created using a bar magnet and a coil of wire.
Let me show you how to do it.

1. Take the fingers on your left hand and curl them into an "o" shape. That's your coil of wire.
2. Then stick out your pointer finger on your right hand. That's your bar magnet.
3. Now, insert your "bar magnet" into the center of your "coil of wire" and repeatedly move it in and out.

SEE the problem?
So, I actually ended the year covering more science topics than I anticipated…
Energy, magnetism...
and reproduction.