A rigorous curriculum refers to a challenging and demanding course of study that requires students to work hard, apply themselves diligently, and meet high academic standards. It typically involves advanced courses in various subjects, such as mathematics, science, literature, history, and languages, which require critical thinking, problem-solving skills, and extensive knowledge. A rigorous curriculum is designed to prepare students for higher education or professional careers by providing them with a strong foundation of knowledge and skills that will help them succeed in their future endeavors.