Growing up in rural Hamakua coast, our school had a public health nurse who visited once a week (if my memory serves me. This was 1946.) She taught us about how to brush our teeth and the importance of this habit.  We had a row of outside fountains on a cement slab and there we were taught the correct teeth brushing routine.  We also ate brown rice at lunch and other healthy vegetables and protein. Interesting that we let that wonderful school benefit slide away into.....what we have now.  Cavities in children due to high sugar juices  and other foods.  Loss of teeth in young adults.  Toothless in later years.