When beginning a unit on enzymes try starting with a few short inquiry-based activities in order to arouse curiosity. This one involves avocado. Students are presented a platter of browned guacamole with a bowl of tortilla chips that they will notice when they first enter the classroom. They are offered to “help themselves”
and, of course, they will be repulsed by the appearance. The students then proceed to hypothesize regarding the cause of the browning and propose means of preventing browning through a relatively short but effective exercise. The entire activity usually takes about one period (about 40 minutes) to complete. It is important to not rush this process. If it takes more than one period to properly to get the best results, then make the best use of your time.