Ellipses

We are working our way through Objects in Motion: Principles in Classical Mechanics by Paul Fleisher. The first lesson is about Kepler's Laws of Planetary Motion.

A key moment for Kepler was when he abandoned circular orbits for elliptical ones, so I designed an activity around ellipses.  I cut a large foam board into quarters, one for each student, and tacked paper to it.  They put two push pins along the horizontal midline of the paper, slipped a string with the ends tied together over it, and drew an ellipse by drawing the string taut with a pencil and circling the push pins.  They moved the pins progressively farther, then closer, and observed what happened to the ellipse.  We discussed how a circle is a special form of an ellipse, just as a square is a special form of a rectangle.

I then discussed Kepler's Second Law and shaded in a pie piece away from the sun and close to the sun.

For the elementary group we skipped the third law.  For the middle school kids I simply wrote the formula and we discussed what it meant, including exponents and proportionality.  They got the fact that distant planets orbit more slowly and related that to the force of gravity.

If you use ExploreLearning Gizmos like we do, there's one on Ellipse and another on Kepler's Laws.

Discount for Upcoming Live Online Immunity Class

I will be teaching a six-week class on the immune system for high school students called Immunity in Sickness and in Health.  The class runs from January 17th until February 21st, Mondays from 1:30 to 2:30 live over the Internet.  All you need is a computer, headphones, and a microphone.  The course costs $90, with a $15 discount for early registration if you register before November 1st.

Physics with Secrets of the Universe

This year we are focusing on physics, and I found a great series of books to introduce middle school students to the subject.  I am using it with our co-op as well.  The series is Secrets of the Universe by Paul Fleisher.  Originally published as a single volume, it is now available as 5 slim books, perfect for moving from elementary into middle school science.  We have started with Objects in Motion: Principles of Classical Mechanics.

This series has so much to like about it.  Fleisher explains concepts in a clear manner with informative examples.  He tells the story through the scientists who first discovered the principles bringing an interesting historical perspective.  He intersperses experiments throughout the text rather than as a separate section.  The graphics are simple and of a single color, yet effective.  It really is a pleasure to read!

The other four books in the series are Liquids and Gases: Principles of Fluid Mechanics; Matter and Energy: Principles of Matter and Thermodynamics; Waves: Principles of Light, Electricity, and Magnetism; and Relativity and Quantum Mechanics: Principles of Modern Physics.

Our TORCH co-op is now up to 6 families and 21 children.  I teach 3 sections of physics, one for middle school girls (4 of them), another for middle school boys (4 of them), and another for older elementary boys (3 of them).  I plan to blog more about out experiences soon!

Planets and Meteors August 12

This Thursday, August 12, is a good night to have an amateur astronomy party.  Every summer the Perseid Meteor Showers dazzle us with their show, but this summer, they have an opening act.

Venus, Saturn, and Mars will all be appearing in the western sky just around twilight along with the crescent moon.  They will be in tight conjunction and easy to see--you won't even need a telescope.

Just as the planets are disappearing, around 10 pm, the meteors will begin.  And with the moon being but a crescent, they will be very easy to spot.  If you rise early, during the darkness just before dawn Friday morning, you could enjoy seeing dozens per hour. 

You can read about it on the NASA blog.

Versatile Blogger Award

Thank you, Annie, from Learn At Every Turn, for this award! She has a great blog with lots of science resources, as well as stuff for other subjects.

For this award:

• Tell 7 things about yourself
• Pass it on to other versatile bloggers

 Here are my 7 things:

•  I love writing; that's why I am a blogger more than anything else in the social media world.
• I very much enjoy teaching, especially through inquiry.
• I could spend all day working on a new Zome model design.
• I would like an iTouch but not until they come down in price.
• I think the most versatile machine would be a tablet PC the size of a netbook--like a laptop and an iPad all in one--and still priced around $300.
• Streaming instrumental music from Pandora is my constant companion at the computer.
• I am Catholic, humbly faithful to the Magisterium, who thinks Evolution is a solid scientific theory that well explains the origins of species to the best of our scientific knowledge today.  That does not make me a deist; God is very much involved with His creation, and has been from the beginning.

I mentioned a lot of great blogs in the recent Blogger of Substance award.  This time, though, I will pass it on to a few, and simply list some other outstanding blogs I love to read but are not really candidates for award memes:

Rockhound Place
Academia Celestia
LaPaz Home Learning

Unity of Truth
The Deeps of Time
Science Notebooking
Notice the Universe