A science lesson: Build machines to crack eggs

Laney Griffith (l) and Liz Koenig

When 11-year-old Liz Koenig was in kindergarten at St. Angela Merici School five years ago, she watched 5th graders use homemade machines to demonstrate "How Do You Crack An Egg?"

The older kids made a variety of odd-looking machines in their science class. The objective of each machine was to crack a fresh egg without anyone touching the egg.

Liz is now a 5th grader. She's getting ready to build her own egg-cracking machine. And a new group of kindergarteners will be watching her efforts.

She said, "When I was younger, the machines looked complicated. But, with what I've done already, making the machine will be much easier."

Diane Steinbruegge is the 5th grade science teacher at the north St. Louis County Catholic school. Virtually all of here scientific lessons are taught with "real world" experiments.

"We have a science textbook but we use it only to look up information. The teaching is done by projects," she said.

This semester the kids studied electronics, the human body and how machines work.

In electronics, the kids learned about circuits and computer language by programming LED panels. They used the same parts that tell motorists how much gas is pumped and how much they owe the station operator.

The kids got to use real gas pump parts. That's because Ms. Steinbruegge's husband works for a company that services real pumps at area filling stations.

Kate Amrein

The final project in that science segment was a competition. The kids divide into teams to see which one could program the most digital numbers and letters in a fixed time.

Ten-year-old Kate Amrein said she had a little head start on the electronics lessons. "My grandfather is an engineering professor at Washington University and he taught me about the positive and negative of electricity," she said.

In the LED competition, she said her team started "hit or miss" with the switch flipping. But, she said, "After awhile, we remembered which switches lit up which parts of the display. It went faster then."

Ms. Steinbruegge often lets the kids try to figure out problems on their own. She believes they remember the lessons better that way.

Another electronic experiment involved the students building battery-powered racecars. There was another competition about which car was fastest on a racecourse.

Liz Koenig's car finished first. But, she admits her car won with some luck. Another team's car was leading but "it swerved off the track just before the finish line," she said.

Eleven-year-old Laney Griffith was another student who enjoyed the racecar building. "It took our team about three or four days to build our car," she said.

With these projects, the students learned about conductivity of electricity. They also learned that all computer programming is based on the numbers 1 and 2. That fits with the positive (+) and negative (-) properties of electricity.

Zach Stealey (l) and Nolan Walsh

Eleven-year-old Zach Stealey said his gas pump team completed 15 of the possible 37 numbers and letters possible. "We kept flipping the wrong switches. Sometimes we flipped two switches at a time," he said.

But, he said, "It feels good when you learn how something works."

Ten-year-old Nolan Walsh said he enjoyed the lessons on the human body. That included a visiting instructor who dissected a real cow heart. Another cow's heart was used to show how blood circulates.

"It's amazing how a little heart could pump so much blood," he said.

Katie Amrein is another of the 5th graders who had watched the "egg-cracking" machines when she was a kindergartener.

She's been looking forward to the project. "I always wanted to build one," she said. She's been thinking of ways to build the machine "so the hammer or heavy object falls and cracks the egg."

She said the eggs will be inside plastic bags. That's so the whites and yolks don't splatter when the egg breaks.

The students were unanimous in their beliefs that "real live" science experiments are better than textbook learning.

Nolan Walsh said science principals are easier to understand when you build something and "realize how it works."

Laney Griffith said, "I understand the science better when I get to do a real project."