Elementary School of Gouves: experiments with gears

by Irini Perissinaki

The earth revolving around the Sun
(theatrical game)

The equipment for the experiments with gears.

20 team bags!

Each team leader receives a bag.

The construction of the base.

Two bases ready!

Compound gear
a spontanous construction

Another spontanous arrangement.

Who needs instructions?

Gears are rather familiar!

They transfer the motion
from the one to the next

Counting teeth
(and following the worksheet)

Counting teeth carefully!

An accurate method.

The white teeth on contact.

On contact again!
(middle and small gear)

Middle and big gear.

It's a bit hard
to construct a gear train.

A correct arrangement.

Mrs Maria Kritsotaki.

And Mrs Olga Paraskevopoulou.

Bevel gears and Moon Phases.

A small demonstration.

And another!

All doing so well!

Amazing motion!

Clever trick!

So simple to perform!

The magic cards!

How do they rotate?

Wonderful toy!

Let's now watch the movie
about the Antikythera mechanism

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This was our second visit to Elementary School of Gouves. The previous one, on October 2014, was a successful cooperation with the most mature students of the school (6th grade) and the two teachers. So, when we got there for a second time on the 26th of September 2016 we felt quite happy to meet our old friends again, and especially the two teachers that invited us, Mrs. Olga Paraskevopoulou and Mrs. Maria Kritsotaki.

The two groups of the 6th grade of the School were arranged in groups of four into the spacious room of multiple uses. A computer and a globe would assist us to investigate some astronomical phenomena: “the seasons”, “the length of daily light”, and “the aurora”. All students “followed” Earth to its yearly journey around the Sun. Interactive applications helped them view Earth from Space as well as the paths of the Sun on the sky during all seasons from different places and latitudes. To understand the reason for Seasons completely, they also played theatrical roles of the Earth revolving around the Sun. But the Sun affects the Earth in many other ways. One that was analyzed on a small movie is the “Space Weather” which varies from “windy” to “stormy” resulting to severe phenomena for the life on Earth but also to the spectacular aurora. Students were really willing to learn and posed quite interesting questions. But the time was up and there were more to do in the second part after the break.

Unlike our first visit, the second part regarded ancient technology and not mathematics. The subject was about the “Antikythera Mechanism”, a 2000 year old computer that was rescued from a wreck in Antikythera and is now exhibited on the National Archeological Museum at Athens. Scientists managed to reveal its interior by tomography and understood its use. This was mechanical computations -done by complicated gear trains- for the moon phases, the eclipses and other events. So, students were invited to experiment with real gears and complete a worksheet. They felt like playing and without reading the instructions some of them stacked two or more gears in the same axis forming compound gears while others created gear trains of two or three gears. A few moments wait for this enthusiasm to settle down and students started to follow closely the instructions on the worksheet. They learned how the number of teeth affects the rotational speed of a gear, why we use compound gears and how to form bevel gears, useful to simulate the moon phases with a small two-colored ball.

All students did their best with the experiments. Indeed, they deserved our small gift which was a magic card with an unspecified shape that was vitalized into two rotating gears when a transparent film with many vertical lines passed over it.

We thank all our friends for the wonderful experience and we look forward to visiting them again!

The teaching material:

A space trip! (space_trip_web_en.pptx)
Worksheet: Activities with gears (Activities.pdf)
The magic card with the rotating gears: (gear_magic_card.pdf)