In my home state of Massachusetts, the legislature recently added a prohibition against discrimination on the basis of gender identity to anti-discrimination laws that cover education. Gender identity is defined int he law to mean "a person's gender-related identity, appearance, or behavior, whether or not that gender-related identity, appearance or behavior is different from that traditionally associated with the person's physiology or assigned sex at birth."
According to the Massachusetts Transgender Political Coalition, which advocated for the law along with GLAD and others, the new law "would make clear that it is illegal for public schools to discriminate on the basis of a student's gender identity, and it would strengthen the school's ability to protect students from violence." This is an important clarification because even though transgender students face an elevated risk of bullying and harassment, federal law does not enumerate protection for gender identity, and not all courts interpret gender-identity discrimination as a subset of sex discrimination that is already prohibited by federal Title IX and others state anti-discrimination laws.
Other states that already have anti-discrimination or anti-bullying laws that protect transgender students are: Connecticut, California, Colorado, Illinois, Iowa, Maine, Maryland, Minnesota, New Jersey, North Carolina, Oregon, Vermont, Washington, and Washington D.C.