Sunday, November 28, 2010

Physics: You spin me round round...




What do bicycles, frisbees, yo-yos, hula hoops, dreidels, and even the earth have in common? They all spin, and so long as they spin the better they are at resisting what gravity is trying so hard to get them to do, which is tumble and fall. The tendency of an object to resist change, is called inertia, or in the case of something spinning, rotational inertia. This week the kids were given plastic plates of different sizes, sticks, and weights (in the form of kippa clips) and were challenged to design the dreidel with the greatest rotational inertia...that's fancy talk for the dreidel that can spin the longest.

Thursday, November 25, 2010

Biology: The birds and the bees


This week we investigated flowers...beautiful displays of nature, so fragrant, so delicate, so easy to cut into lots of tiny pieces! Yes, this week ten flowers donated their bodies to science, so that your children could learn about the birds and the bees...literally.

The kids dissected lilies and matched each part with a description of the role it plays in making more flowers. Pollination, fertilization, ovules, and anthers, we covered it all...a comprehensive discussion of the facts of (plant) life.

One of the reasons we introduced this topic now is in preparation for an exciting international research project we will be joining run by an organization called iEARN. Classrooms around the world will be planting daffodils and other bulbs during the last week of November. We will be collecting data on temperature and other variables, and over the next few months we will be tracking the daffodils' growth. Throughout the project we will be sharing our results with other participating schools and groups. To read more about the project, you can check the following link http://media.iearn.org/projects/daffodilsandtulips.

General Science: It's a gas!


For our experiment this week, we did an oldie but a goodie...
what happens when you mix baking soda and vinegar?

Having some experience with making volcanoes or otherwise messing around in the kitchen, the kids guessed correctly that the combination would produce, in their words, "AN EXPLOSION!!!" (Aren't you glad this happens at my house and not yours?!)

This week we took it one step further to show that the combination of baking soda and vinegar produces a gas that can put out a fire. Passing a lit candle over baking soda had no effect on the flame. Same deal for the vinegar, but when you combine the two, and you get your EXPLOSION (i.e. bubbles), passing the candle over extinguishes the flame. Why does this happen? Mixing baking soda and vinegar is a chemical reaction, and as such, produces something new, carbon dioxide. That's what the bubbles are, and they have the property of putting out a fire and that's why they carbon dioxide in an actual fire extinguishers. Cool, huh!?

Tuesday, November 16, 2010

General Science: Mixing Iron and Sulfur

This week we started learning some chemistry. Using a microscope and a magnet the kids explored the properties of 2 elements: sulfur and iron. Then they combined them and determined whether they had performed a physical change or a chemical change.

Here are some of the high points of their results:

iron: black, magnetic
sulfur: yellow, smelly, not magnetic
iron + sulfur: grayish yellow, smelly, BUT easily separated from each other with a magnet

Physical or chemical....you decide!

Thursday, November 11, 2010

Physics: Magnets


This week the kids investigated magnets. They tested various materials to see which ones are magnetic, compared the strengths of different magnets, learned how to turn iron nails into weak magnets, observed the effects of magnets on compasses, and used iron filings to observe magnetic fields.

Tuesday, November 2, 2010

Biology: Testing for organic compounds



This week we discussed organic compounds. First we dispelled any myths about organic compounds being any healthier than regular old compounds. Likewise, if someone tries to charge you more money for an organic compound, don't fall for it! In chemistry, organic means relating to living things and containing lots of carbon atoms.

We used chemical and physical tests to find out whether the 6 foods in question (water, veggie soup, milk, egg, margarine, and oatmeal) contained proteins, fats, or carbohydrates (starches or sugars.)

Physics: Quiz-show Part II

This week the kids finished their quizboards - hopefully by now you've seen them, played with them, and hopefully not broken them! This was NOT an easy project. It took a lot of patience and attention to detail, checking and rechecking connections in the circuits, but in the end it paid off. "Operation's" got nothing on these quizboards.

If you haven't already, please register your kids and send in checks asap. Kids who aren't fully registered by next week will have to work off their debt at the Large Hadron Collider, tracking the subatomic chaos of protons colliding 300 feet underground in the bowels of this giant particle detector.