Friday, May 11, 2012

Favorite Website: Access Excellence

Originally posted on March 19, 2010

There's another great collection of life science activities found at Access Exellence. I have spent most of my time going through the Fellows Collection (1994, 1995, 1996), but the rest of the site is worth looking at as well. As with all my favorites, some individual activities will be featured in their own posts.

The activities found in this section of the website have been submitted by high school teachers participating in the Access Excellence program. As such, the activities were designed for high school students. However, many of these activities are very easily adaptable (or usable as is) for lower grade students.

Wednesday, May 9, 2012

Inertia: Knock the Penny Out

Originally posted on March 18, 2010

Make a stack of 5 or 6 pennies. Use another penny to try to knock the bottom penny out, while keeping the rest of the stack in tact.

Go a step farther and make your stack of pennies on a piece of paper. Trace a circle around the pennies. Now, try to keep the stack of pennies in the circle after you knock the bottome one out.

Monday, May 7, 2012

Cellular Respiration in Yeast

Originally posted on March 17, 2010

Place some yeast, sugar, and warm water in a flask (or bottle with small neck). Quickly place a balloon over the flask opening and allow it to sit for the class period (or longer).

At the end of the period, you will find the balloon has inflated. It is filled with carbon dioxide released during cellular respiration.

You can prove that it’s carbon dioxide and not oxygen: light a wood splint or popsicle stick on fire and then blow it out so that it’s just glowing. Release the contents of the balloon onto the glowing splint. If it’s oxygen, the splint will return to burning; if it’s carbon dioxide, it will go out.

A note about my pictures... In the picture of the initial set-up, the bottle only has a little water in it. It wasn't enough - the yeast respirated, but the carbon dioxide they emitted took up the remaining space in the bottle and didn't make it to the balloon. I redid the experiment, filling the bottle much fuller, which resulted in an inflated balloon; but I didn't retake the set-up picture.

Friday, May 4, 2012

Earthquakes & Plate Tectonics: Plot Earthquake Data

Originally posted on March 16, 2010

Use the US Geologic Society website to print out a copy of the most recent earthquakes. Provide students with a world map with lines of latitude and longitude clearly marked. Have students plot the points at which the earthquakes occurred. Compare the plotted data to a map of the tectonic plates. If enough data points are plotted, you will see an outline of the tectonic plates form, as most earthquakes occur along those faults.

If you wish, to get more data plotted more quickly: print out the world map on overhead transparencies for each student. Have each student plot several points on their transparency. Then stack the transparencies on top of one another to create a single map.

Wednesday, May 2, 2012

States of Matter: Bouncy Balls

Originally posted on March 15, 2010

Empty a large, clear container (large pretzel or snack mix jugs). Fill part way with rubber bouncy balls. Use to demonstrate states of matter as follows:

Solids: barely shake the container, just enough to cause the balls to jiggle, but keep them in their place. The atoms/molecules in a solid possess kinetic energy, but not enough to remove any individual atoms/molecules from the group.

Liquids: shake the container a little harder, so the entire “clump” moves together. The atoms/molecules in a liquid posses more kinetic energy than those in a solid. Liquids can change shapes, but the atoms/molecules stay “attached” to one another.

Gas: shake the container even harder, so that the balls begin to bounce around the container, independent of one another. The atoms/molecules in a gas possess a large amount of kinetic energy. They will bounce around to fill the space they have available.

If you don't have a large container, or enough balls for a large container, you can make a smaller version (as seen above). It's probably not quite as effective as a demonstration as the larger version, but it works.