The requirements for becoming a teacher were always straightforward: Earn a college degree in education, take enough classes in your area of specialty, practice your teaching skills for a semester as a student teacher. Politicians have added a new skill this year in some states: Be a mind reader. That’s what teachers in a Texas school district concluded recently after receiving guidance for how to comply with a law passed this summer by the Texas Legislature and signed by Texas Gov. Greg Abbott. The law, known as H.B. 3979, restricts how topics like race, sex, diversity and discrimination are taught and discussed by Texas public school employees and in textbooks and other course materials teachers use. A companion bill, S.B. 3, discourages teachers from addressing current events in their social studies classes.