the day for my daughter's school visitation

Last Saturday, 16 April, I and my wife went to our daughter's elementary school. Although our son, who is now in second grade in junior high school, was used to hate we visiting his elementary school, she wants us to visit her school. Anyway, we observed her science class on burning. In the black board, four figure of a burning candle and a bottle without bottom on a table were drawn. The first showed that the bottle covered the candle without no opening between the bottle's bottom section and the surface of table, and a lid was put on the bottle. The second explained that although the relation between the bottle and the table was same as the first, a lid was not put on the bottle. In the third and the fourth, there was an opening between the bottle's bottom section and the surface of table, and in the third a lid was put on but in the fourth was not. For each figure, her teacher asked his students, "Which do you think the candle continue to burn or go out?". And he actually performed each experiment in the front of his students.
When our daughter came back to home, I asked her, "What have you learned from the lecture?". "I learned that a material could not burn without making way for air, she said. Then I continued to ask her, "If only you want to make a path for air, is it enough to make an opening between the bottle and the surface of table like the third figure?". "I don't know, I learned only about a path for air", she answered. I thought that her teacher planed the four experiments for his students understanding that burning consumed oxygen and emit carbon dioxide, and carbon dioxide was heavier than oxygen. I thought her teacher should make his students consider why the both upper and bottom openings were needed to burning the candle in the bottle. In Finland, I wonder what kind of lecture is performed on this content.