# Building (math and science) Knowledge

There are different types of knowledge. To know how a square is defined is different than knowing how to identify one. These are different that knowing how to draw one with ruler and paper. Or construct one with compass and straight edge.

A square is a pretty simple example, but when it comes to ramps, bridge, exploring mass and rotation, there’s being able to answer questions about it, and then there being able to build object to create examples, non-examples, and solve challenges. And it can help to have the right tools.

My office recently got a set of Keva Planks. Now, I’ve gotten to see these blocks in action a number of times and they are pretty cool. First, there is almost no learning curve. The blocks are all exactly the same. There’s no connecting pieces or fasteners or adhesive. There’s nothing to them. But with them you can build ramps and towers, polygons and prisms. They set up easily, the clean up easily.

Full-disclosure: They aren’t free. (Cheapest place I’ve found them is Amazon… 400 blocks for \$90). Ordinarily, I don’t make a point to advocate for expensive tools, but in this case I think it could be money well spent based on the needs of the location. Also, they are durable and shareable. One department or grade level team could probably make good use with one to share.

Anyway, it’s worth looking in to as they allow us to explore types of knowledge that we otherwise might not be very well equipped to explore. (Particularly with those Next Gen engineering practices that are starting to become a reality in many states.)

For another look, here’s my latest podcast: Instructional Tech in Under 3 Minutes #5 – Keva Planks.

# Kitchen Science: A glass bottle, an oven, and some ice water

So, today I did a little science in my kitchen. I learned some stuff and I wanted to try it out. And I’ve got a 5-year-old and an 8-year-old who are very willing to be perplexed.

Before I get into the story, I have a question for you.

Imagine you heated a glass bottle (maybe the 12-16 ounce variety) in the oven at 450 for 10 minutes or so. Then you took it out, turned it upside down and placed it quickly about an inch or so deep in a sink of ice water.

What do you think would happen?

We did this exploration in the kitchen. It led to some good perplexity and some great wonderings.

In my next post, I’ll share what happened.

# Physics, a helicopter and cameras

First watch this (and be amazed… well, if you’re anything like I am.)

So, when the students can get past the idea that there is some foul play involved, then it becomes a wonderful opportunities to discuss the idea of frequency.

Frequency is an odd discussion because it’s got a strange unit. The “per time” can be a little challenging for students to wrap their heads around.

And the opportunity that this video provides is that here, we don’t need to immediately concern ourselves with the quantitative value of the frequency (maybe 300 RPM for the helicopter rotor, for example, or 5 frames per second on the camera), but we can begin with the qualitative value of the frequency (that the frequencies, whatever they are, are the same.)

And then it opens the door for them discussing some quantitative issues. For example, the fact that the standard unit of frequency (the “per unit time”), obviously isn’t constant. So, the helicopter rotor is RPM and the camera shudder is typically in frames per second (at least, I think. Not a photographer…) So, you’ve got some nice dimensional analysis opportunities.

Where could you take this next?

One thing’s for sure, I’d hate to waste a video like this. Fully captivating, and it only costs your 30 seconds of class time.

# The Blue Man Group did high school physics teachers a favor.

A nice engaging intro to your unit on sound waves.

And as an applied project, perhaps students could make a smaller version. Paper towel rolls? Saran wrap? rubber bands?

Anyway, a lot of possibilities when a video is this well done.

# Rotational Motion… or tangent lines.

All right team, let’s do something with this:

Obvious choices are rotational motion, tangent lines, centripetal force.

I just love the authentic demonstration, particularly when the sliders let go. Tracing their motion (a straight line tangent to the circle at the point they let go…)

This is just too good to ignore. Enjoy it!