Posts

First week highlights: murdered teddy bears, fun with puppies, trail cameras, and perfect rectangles

Image
It was a great first week and a half back at Tok School. Classes have been off to a crazy but wonderful start! It's great to see so many familiar faces, exchange stories, and see that my 8th graders have become highschoolers!

Updates: Biology and Physics started off with a "bang" (figuratively, I promise) this week in our introduction to science units. As I set up every year, a "crime scene" was constructed in the lab and the students used their knowledge of the scientific method (observing, making a hypothesis, experimenting, and analyzing and writing their results) to solve the mystery. It was a little bloody, but fortunately no actual teddy bears were harmed in the making of this lab :-). To see if you can solve the crime for yourself, see the full lab here!







Biology class also started on our moose and wildfire project, which we will update you on more this week. For this project, we are studying the relationship between wildfire, plant succession, and moose …

Breaking (popsicle stick) bridges

Kyle Litwack's physical science project: engineering a popsicle stick bridge. He tested two different models, a single truss (strong) and a more flexible, suspension model (for looks). The results he filmed below. Thanks for sharing the video, Kyle.





"Got Science?" event finale

Image
Hopefully I'll have some more of our "Got Science?" event to share, but in the meantime, here is a video of our liquid nitrogen explosion finale (thanks Sarah Richards for filming, Diana Ervin for picking up the LN2, and Kyle, Leeanna, Trinity, Riley, Gabriel, and Cody for helping out with the event!)


Fun with Liquid Nitrogen

In preparation for our "Got Science?" science demonstration this Thursday, we spent part of last week experimenting with liquid nitrogen. One of the most impressive experiments is to confine liquid nitrogen in a bottle. Because liquid N2 boils at -321 F, it generates a massive amount of steam (and pressure). Eventually, the bottle bursts in a powerful explosion. When confined and arranged under 1000 ping pong balls, the result is pretty neat! We also succeeded in creating water bottle rockets, deflating balloons in liquid nitrogen and getting liquid air, and other interesting projects. Thanks to Kyle Litwack for this video.


Chemistry - What's in a Bond?

Image
What's in a bond? If starch were not covalently bonded, would it still smell as sweet?

OK, probably not, considering it burns. And yes, probably about 98% of people did not catch my hopeless Shakespeare pun.

In this lab last week, our chemistry class investigated bonding, the force holding atoms together. As it turns out, we can determine covalently bonded (sharing of electrons) structures from ionically bonded (electro-magnetically attracted) structures by their melting points and conductivity in water!

Armed with our homemade bunsen burner (courtesy of Mr. Monroe - thanks!) and a multimeter, we put three compounds to the test.

The ionic compound (NaCl) conducted electricity in water and only melted at a high temperature. The covalent compounds did not conduct electricity and melted much sooner. 









Highlights from Physical Science projects

Image
See a few pictures of some Physical Science projects below. Thanks Brooke for the excellent photos!






7th Grade: Ecology and Ecosystems

Image
For our unit on ecosystems, we are studying biodiversity. Our question last week was: are trees an indicator for overall ecosystem biodiversity? To find out, we looked at the biodiversity of various forests and how they match with overall ecosystem biodiversity.

For example: Borneo, one of the most biodiverse places on Planet Earth, hosts 700 individual species of tree in its forests! (Mind you, that's trees alone, not including all other types of plants.) To see how we compare, we ventured into the Deep Dark Forests of Tok to collect as many different species of tree as we could find.

Well... It wasn't very hard. Four to five species later, we were back in the lab noting differences between white spruce, aspen, birch, and possibly two types of willow.

That's right... About four total species. So why - what factors affect biodiversity? (Hint: sunlight and water sure do help!) See the pictures below from Kaitlyn, our class photographer last week.