Case
Sex ed

How can I reach students that have overprotective parents and still provide them with necessary safe sex education?

Solution #1
Make sure you double check with your school. Maybe sending a note home to the parents and making sure they are comfortable with the material.
Solution #2
Check your school's policy. Without the parent's permission, there's not much you can do.
Solution #3
Unfortunately there isn't much we can do about that. If a parent wants their kid to not learn about those things, it is usually because they feel their child is not ready for it or they want to approach the lesson themselves at home.