Education should cover essential life skills, including laws and legal rights, mental health fundamentals (such as healthy boundaries, recognizing abuse, self-esteem building, emotional regulation, growth mindset, assertiveness training, and other communication skills), personal finances, and nutrition. Leaving these topics up to parents is unwise because most people are unskilled in these areas. Education has to begin somewhere.
I believe every widespread problem in society rooted in education deficits should be addressed in schools, as long as the content is age-appropriate. I can't think of exceptions currently, but I'm sure there are some; there always are exceptions in life.
For example, one main cause of poverty is the lack of proper financial education, which often comes from impoverished parents. So, why are we leaving financial literacy to be taught by parents who will almost certainly instill ways of thinking that perpetuate poverty? The wealthy look at money very differently from the vast majority, and that's why they're wealthy—not vice versa. If more people in a country had money sense, the country's economy would also improve.
Gifted children also need to be better supported.
Additionally, the Pledge of Allegiance should be removed.