The term rigor is widely used by educators to describe instruction, schoolwork, learning experiences, and educational expectations that are academically, intellectually, and personally challenging. Rigorous learning experiences, for example, help students understand knowledge and concepts that are complex, ambiguous, or contentious, and they help students acquire skills that can be applied in a variety of educational, career, and civic contexts throughout their lives.

While dictionaries define the term as rigid, inflexible, or unyielding, educators frequently apply rigor or rigorous to assignments that encourage students to think critically, creatively, and more flexibly. Likewise, they may use the term rigorous to describe learning environments that are not intended to be harsh, rigid, or overly prescriptive, but that are stimulating, engaging, and supportive.

In education, rigor is commonly applied to lessons that encourage students to question their assumptions and think deeply, rather than to lessons that merely demand memorization and information recall. For example, a fill-in-the-blank worksheet or multiple-choice test would not be considered rigorous by many educators. Although courses such as AP United States History are widely seen as rigorous because of the comparatively demanding workload or because the course culminates in a difficult test, a more expansive view of rigor would also encompass academic relevance and critical-thinking skills such as interpreting and analyzing historical data, making connections between historical periods and current events, using both primary and secondary sources to support an argument or position, and arriving at a novel interpretation of a historical event after conducting extensive research on the topic.

While some educators may equate rigor with difficultly, many educators would argue that academically rigorous learning experiences should be sufficiently and appropriately challenging for individual students or groups of students, not simply difficult. Advocates contend that appropriately rigorous learning experiences motivate students to learn more and learn it more deeply, while also giving them a sense of personal accomplishment when they overcome a learning challenge—whereas lessons that are simply “hard” will more likely lead to disengagement, frustration, and discouragement.

One common way in which educators do use rigor to mean unyielding or rigid is when they are referring to “rigorous” learning standards and high expectations—i.e., when they are calling for all students to be held to the same challenging academic standards and expectations. In this sense, rigor may be applied to educational situations in which students are not allowed to “coast” or “slide by” because standards, requirements, or expectations are low. In these cases, rigor is connected to the concept of educational equity, the belief that all students—regardless of their race, ethnicity, gender, socioeconomic status, English proficiency, or disability—should pursue a challenging course of study that will prepare them for success in later life. For example, students of color, on average, tend to be disproportionately represented in lower-level classes with lower academic expectations (and possibly lower-quality teaching), which can give rise to achievement gaps or “cycles of low expectation” in which stereotypes about the academic performance of minorities are reinforced and perpetuated because minority students are held to lower academic standards or taught less than their peers (for a related discussion, see stereotype threat). Enrolling students of color in “rigorous” academic programs that hold them to high academic standards is one way that educators may attempt to close achievement gaps and disrupt the self-perpetuating nature of low expectations.