Most of the teachers I know would prefer to spend five minutes a day doing supervised brushing than watch their kids end up in agony in hospital because their teeth are rotting out of their heads.
As the keeper of a just turned 6 year old, 5 minutes seem somewhat fanciful. I can't imagine rustling 30, five year olds, making sure they have clean brushes, tooth paste, and somewhere to rinse, spit and clean up in anything like that time.
Most of the teachers I know would prefer to spend five minutes a day doing supervised brushing than watch their kids end up in agony in hospital because their teeth are rotting out of their heads.