The boys had the opportunity to scuba dive yesterday.  It was an introductory course offered by the local dive shop. They learned how to equalize their ears, remove, clear, and replace their air source, and how to check their air gauge to make sure they had enough air. They were in the water for an hour and a half, and underwater - breathing! - for more than half that time. I was able to watch from a viewing window. They are now pining for a dive certification course - which costs substantially more than the $15 introductory lesson…