Abstract
This activity was designed to stress importance of oxygen for humans with a special focus on first aid. Two activities were tested.
It starts with brainstorming about air, its importance, its composition etc. The teacher directs the discussion to oxygen.
As the first activity, students encounter production of oxygen. They use an oxygen sensor to measure the production of oxygen by a plant under different conditions (dark, daylight, lamp).
The second activity concerns human breathing. Students use the oxygen sensor to measure proportion of oxygen in the air in the lab, and later in the air they exhale.