Waldorf schools

Last evening, one of the new Waldorf schools had a "workshop" to educate parents about the benefits of the Waldorf system. True it is better, but the teacher who spoke made a couple of errors which made me think. The basic idea in these schools is that the teacher introduces concepts of say math or science or history or whatever during the course of a sort of a talk on anything...she in particular said she brings in the Pythogoras theorem when discussing Egypt, and discussed the advent of the Mughals with regard to the building of the great wall of China. All very well, but she also mentioned how she discusses the composition of air...oxygen, nitrogen and hydrogen...now why hydrogen? is that just aslip or does she not know that the % of hydrogen is rather small? she also said that the % of oxygen must be maintained (good so far) because excess oxygen makes our skin age faster. Now of course, yes, oxidative processes do age us, but is that relevent? Such things give the children totally wrong ideas...it would mean the world is designed for our benefit....haven't we done enough damage to the world without inculcating such attitudes in kids?---- and even if you wish to be anthropocentric, excess oxygen would burn everything up....forest fires we have seen so far would be kids' bonfires in comparison--but aging skin??
This makes me wonder if leaving things to teachers is such a good thing...many school teachers are learned, well read, but many are not.
This method puts too much on teachers and many may not be able to rise up to it.