Title IX prohibits sex discrimination in schools and requires them to address sexual harassment against students. Sexual harassment includes unwelcome sexual advances, requests for favors, and other verbal or physical conduct of a sexual nature that denies or limits a student's ability to participate in or benefit from a school program. Schools must consider factors like the nature of the conduct and context to determine if it constitutes sexual harassment. Sexual harassment of a student by a teacher violates Title IX, and schools are obligated to take immediate action in such cases while respecting employees' due process rights and confidentiality standards for complainants.