The candle burning experiment is usually conducted in lower secondary classes to prove the (about) 20% oxygen in air. The aim of this paper is to show that teachers misinterpret the results of the experiment to satisfy the objectives of teaching this experiment. However, when the results of this experiment are interpreted correctly, the objectives for conducting this experiment at this level are not satisfied. It is therefore proposed that this experiment is not suitable at this level and should not be taught at this level. Teaching this experiment to meet the desired learning outcomes is a waste of time and adds to misconceptions. However, the simple experiments reported in this paper may be used to develop critical thinking and creativity in secondary school students. Further research in identifying pieces of knowledge for which similar mismatches between factual (scientifically accepted) and actual (misinterpreted results) knowledge claims is recommended. (Contains 6 figures and 4 tables.)