TISA Hot Air Ballooneys: Race to Enter & Fuel Analysis
Deciding on the Ballooney Baku "race" to enter their tissue-paper hot air balloon in, identifying the kind of fuel necessary to win the race, and analyzing the fuels.
The Burning Issue of a Candle
A simple experiment involving inversion of a conical flask over burning a candle in a dissection tray with some water can be a stimulus for open-ended, really really fun, very very challenging -- to both students and teachers alike -- problem, covering some fundamental high school chemistry.