Science circus brings explosive experiments to Halstead Elementary

By SANDRA ZIEHLKE
Special to Leader-Press
 
Children of all ages love the circus. Students and staff at Hettie Halstead Elementary were treated to a different kind of circus that had students hammering with rock-hard bananas and teachers breathing smoke out of their noses and mouths.
Third Grade Science teacher Swantje Drayton invited the Austin Physics Circus to present a one-hour show that is free of charge to schools and follows the Texas Knowledge and Skills curriculum. Both presenters are students at the University of Texas at Austin and are pursuing graduate degrees in the field of physics. Madisen Holbrook is in her fourth year as a nano-electronic materials physicist while Chuck Burton is in his second year as a high-energy elementary-particle physicist. 
Both scientists demonstrated a variety of highly engaging experiments that required hands-on student participation while using student-friendly terms. Students and staff witnessed a gas-to- liquid phase transition of a balloon dipped into liquid nitrogen. During the dip into the liquid nitrogen, the gas in the balloon is cooled and transitions to liquid. As a result, the balloon shrinks. 
During a Van de Graff generator electricity experiment, fifth grader Devon Perez astonished the presenters with his correct hypothesis.
“I predicted that the pie tins would float up off the generator because of the charged particles pushing them up,” Perez said.
Third grader Zuriel Harrison witnessed the transition from a liquid to a solid as he used a liquid nitrogen-dipped banana to hammer a nail into a wooden board. Teachers Kelley Grubb, Laura Murphree, and Aubrey Darthard consumed liquid nitrogen frozen graham crackers which literary made them blow smoke out of their mouths and noses. Further experiments followed involving states of matter, gasses and pressure, and electricity. The experiments were not only fun to watch but also prompted students to ask questions and hypothesize about possible outcomes.
 4th Grader Timothy Groundtree was astounded by what he witnessed.
“I couldn’t understand why the beaker did not break from the cold temperatures of the liquid nitrogen.”
The physicists saved the most exciting experiment for the closing act of the circus, the soap explosion. The presenters dumped liquid nitrogen into a trash can filled with soapy water forcing the volume to change during vaporization and causing a big explosion as the grand finale of the Physics Circus.