Monday, December 22, 2008

Bird of the Week - XVl

This week's "Bird of the Week" is the House Sparrow. The House Sparrow is not native to North America. It was introduced into Brooklyn, New York, in 1851 and has now spread successfully across North America. The House sparrow is the noisy sparrow-like bird you see nesting in store signs and in and around buildings. The House sparrow almost always stays near people and their buildings.
The House sparrow is a small, stocky songbird with a thick bill. It is about 6 -7 inches long with a wingspan of about 7 - 10 inches. It has wing bars and an unstreaked chest. The male has a black throat and white cheeks.
The House sparrow lives here year round and eats seeds from bird feeders, weed seeds, and insects.
Photos from All About Birds.

Wednesday, December 17, 2008

Solids, Liquids, & Gases

To demonstrate that matter expands when heated and contracts when cooled, we did several activities and demonstrations.
In the “Ball & Ring” demo, we heated a brass ball in the Bunsen burner and then tried to put the ball through the brass ring. It wouldn’t go through because it had expanded. We then plunged the ball into cold water and then tried to put the ball through the ring, and, it did! The ball had contracted when thermal (heat) energy, was taken away.
To show that liquids expand when heated and contract when cooled, we did the “Mood Ball” activity. Working with their partner, the students put the “Mood Ball” into hot water and observed the level of the water in the tube go up, or expand. Next, they placed the “Mood Ball” into ice water and observed the level of water in the tube go down, or contract. The students discussed how this activity was similar to how an alcohol thermometer works.
In the “Flask With A Balloon” demo, we put a balloon on a flask and then put the flask on a hot plate. After a while, the balloon began to “grow”, or expand. We then placed the flask on the window sill to cool and after a while, we saw that the balloon had “shrunk”, or contracted back to its original size.
Matter expands when heated and contracts when cooled. The volume increases when heated and decreases when cooled.

Monday, December 15, 2008

Bird of the Week - XV

This week's "Bird of the Week" is the Sharp-shinned Hawk. If you are a back yard bird feeder, you have probably had a Sharped-shinned hawk zip through your yard attempting to catch a bird. The "Sharpies" are built to chase and catch small birds. They will hunt birds using a low, stealthy approach-flight or after a short chase. They use cover such as trees and bushes, and man-made structures like fences, to conceal approach. They will catch birds at bird feeders, too.

The Sharp-shinned hawk is a small hawk with a long, barred tail that ends with a square tip. Its wings are short and rounded. The adults have a blue-gray back and wings with reddish barring on their underparts.

The female Sharp-shinned hawk is about the size of a Blue Jay or a Mourning Dove, with the female bigger than the male.

Sightings of Sharp-shinned hawks in our area have dropped over the past 10 years. We are now seeing more Cooper's Hawks at feeders. It can be a challenge to tell the two species apart.

Thursday, December 11, 2008


We have begun a study of Matter. Matter is anything that has weight and takes up space. Matter is made up of tiny bits called molecules. Molecules are made up of even tinier particles called atoms. Matter can be found in 4 states, or phases. Solids, liquids, gases, or plasma. The students had the chance to do a little bit of role playing. They played the roles of the molecules in a solid, liquid, and gas. It was really interesting to see the kids figure out that when they were a gas they could spread out and have more energy. It was especially funny when they were a solid and had to gather really close together.

We drew illustrations of how the arrangements of molecules in solids, liquids, and gases are different from one another. The molecules of a solid are packed tightly together and they cannot change position, they vibrate in place. The molecules of a liquid are further apart from one another than in a solid and can slide past each other and change position. This is why liquids take the shape of the container they are in. The molecules of a gas are even further apart than those of a liquid and they can easily spread out to all parts of a container.

Some similarities about the molecules in solids, liquids, and gases are that they all have energy, they all move, and that there is space between the molecules.

We have begun exploring what happens to solids, liquids, and gases when thermal (heat) energy is added or what happens when heat energy is taken away (made cooler). To demonstrate thermal expansion and thermal contraction, we did the Ball & Ring demonstration. Take a look at the video of it!

Monday, December 8, 2008

Bird of the Week - XlV

This weeks' "Bird of the Week" is the Hairy woodpecker. The Hairy woodpecker is one of the most common woodpeckers in North America. It comes readily to feeders where it will eat suet(beef fat) and seeds. The hairy woodpecker is a medium-sized woodpecker, about 7 - 10 inches long with a wingspan of approximately 13 - 16 inches. It's plumage (feathers) are black and white with a plain black back. It's bill is thick and rather long. The male has a red patch on back of it's head while the female has a black patch.

Identifying a Hairy woodpecker from a Downy woodpecker can be tricky. One of the best ways to tell them apart is to look at the proportion of the bill to the head length when viewed from the side. The Hairy Woodpecker's bill is usually greater than one-half the depth of the head. The Downy Woodpecker has a bill less than one-half the depth of the head. Click here to see a good article about telling the two birds apart. To learn more about the Hairy woodpecker and to hear it's song/call, click here.

Photos taken from All About Birds.

Monday, December 1, 2008

Liquid Density - Fresh Water vs. Salt Water

In today's activity, the students investigated if there were any difference in the density of fresh water and cold water. The fresh water was colored yellow and the salt water was colored green. Eventually, the kids determined that salt water is more dense than fresh water.

Bird of the Week - Xlll

This week's "Bird of the Week" is the House finch. The House finch is a bright red and brown-striped bird of the cities and suburbs. The House Finch comes readily to feeders. It also breeds in close association with people, and often chooses a hanging plant in which to put its nest.

The House finch is a medium-sized finch, about 5 - 6 inches long with a wingspan of about 8 - 10 inches. The male is bright red on it's head, chest, and rump and the female is brown and striped. It has a short, thick bill that is rounded on the top edge. It has two, thin, white wing bars. The House finch can easily be confused with the less common, but similar looking Purple finch

The House Finch was originally a bird of the southwestern United States and Mexico. In 1940 a small number of finches were turned loose on Long Island, New York, and they quickly started breeding. They spread across the entire eastern United States and southern Canada within the next 50 years. In the early 1990's, the House finch population was greatly reduced due to an avian (bird) form of conjunctivitis.

The House finch forages (feeds) in small flocks, usually in trees, but often on ground and uses bird feeders extensively. It will eat buds, seeds, and fruits.

To learn more about the House and to hear it's song, click here.

Photos taken from All About Birds.