One of the most important subjects there is. We live with our bodies every day. Yet we are so ignorant, about health, and infection, and disease, and prevention. And when we get sick, or when things break down, we're at the mercy of the health professionals. Because we learned zip about our bodies in high school.
Most people know zip about their physical health.
We know even less than zip about our spiritual health. A lot of people today are interested in genealogy, as a hobby. They go around looking up information about their ancestors, and write it all down and pass the information on to other people. A lot of people I know are passionately interested in politics, and economics, and technology. I can hear a couple of objections already.