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Parkway Central Middle School kids got an unwanted science lesson at the end of their hot-air ballooning class.

All year, eighth grade kids have been learning math, science and even history lessons linked to making and flying of hot air balloons. Last month, the kids held a mass balloon launching in the school yard.

A total of 120 eighth grade kids launched 30 balloons to see how high and far each of their home-made balloons can go.

Usually, in the spring, the outside air temperature is cool, especially in the morning when the launch was held. But, this year, the temperature on launch day was in the 80s.

Teacher Judy Green said, "There was too much temperature outside. And not enough inside the balloons."

That meant the temperature of hot air inside the balloon wasn't too much different than the outside air. It's that inside-outside temperature difference that gives a balloon it's "lift." That's the science lesson the kids would have just as soon not learned.

As a result, many of the 30 balloons just barely lifted off before they came back to earth.

But, the balloon of Ariehal Stephenson, Colin Schwartz and Kyle Meldrum did win the height and distance award. They also got a special bonus--their balloon traveled high and long enough to land on the top of the Parkway Central Middle School.

That meant the student "balloon chaser" team had to go up on the roof to retrieve their balloon.

Launch day involves a lot of organization and teamwork between students, teachers and parents. Also, there's special equipment and scientific instruments.

Math teacher Judy Green was the overall coordinator. She was on duty early in the morning to start the charcoal fire in a big barrel barbecue pit. Once the briquettes are hot, they are put into specially built ovens that vent hot air into the balloons.

Teams of parents held the tissue-paper balloons over hot air vents until they were filled.

Then, students on each balloon team measured the flight pattern with a scientific instrument called a "theodolite." That gives a reading to let the kids determine how high the balloon went.

Another team member had a stopwatch to see how long the balloon stays in the air.

The team of Kamryn Colatruglio, Brittane Todd, Jennifer Guenther and Kinsey Coker was one group that got it's balloon into the air early in the day. That was before the charcoal was its hottest but before the outside air got too hot.

Asked what she learned about ballooning, Kamryn said, "I know you can't have holes in the balloon and expect it to fly." She had to patch a hole in their balloon just five minutes before the launch.

Kinsey was in charge of timing the balloon flight. It stayed in the air 21 seconds.

Brittane said she liked the teamwork involved in building and flying the balloon. Jennifer said, "I always knew that hot air was lighter and this project proved it to me."

The balloon launching was done in five different shifts.

There was even a student crew armed with fire extinguishers to put out any fires that might be started by the hot charcoal. None of the balloons caught fire but there were a couple small grass fires near the hot-air loading ovens.

Mary Armstrong was one of the extinguishing crew that answered the fire alarm. She used a dry extinguisher to douse the small flames.

Kyle Feigerbaum and Kevin Moss were on one of the balloon-building teams. Kyle said it took their team about two days to put the tissue-paper balloon together. They had to glue the paper panels together.

The top of the balloon was tied shut and the bottom was fitted around a wire hoop that kept it open so the hot air could inflate the balloon.

Then, each balloon had to undergo a "hair-dryer" test. Heated dryer air was blown into the balloons to they could be checked for holes and leaks.

But, on launch day, there needed to be plenty of last-minute patches added. Sometimes a hole was poked into the balloon when it was being filled. In other cases, the original glued joint gave way.

Other stories on Parkway Middle hot-air ballooning Young Saint Louis.com has followed the Parkway Central Middle School hot-air ballooning class since the start of the 2000-2001 school year. Last October, we told about how Parkway teachers Judy Green and Tony Ambrose used the building of hot-air balloons to teach lessons in math, science and history. (If you'd like to read the first article, click here.) In February, we featured an article how the Parkway kids put together a teaching website, video and CD on the hot-air balloon classes. The lesson plans could be used by other schools wanting to use this subject matter. (To read this second article and learn how to get the teaching lessons, click here.) The Parkway teachers and kids also joined with Young Saint Louis.com to make a joint presentation in February, 2001. The presentation was at the 2001 Midwest Educational Technology Conference in downtown St. Louis.