The term "rigor" in education often evokes resistance due to its inconsistent definitions and widespread misconceptions. This study introduces and validates the RIGOR Walk framework, a research- and practitioner-informed tool designed to define, observe, and enhance rigorous learning environments across classrooms. The framework is grounded in five core components--"Relationships", "Instruction", "Goals", "Organization", and "Relevance"--each supported by observable indicators aimed at promoting deep thinking, academic risk-taking, and meaningful engagement. Following iterative rounds of expert feedback, the framework was refined and validated in three phases: (1) establishing face validity through crowdsourced expert critique, (2) analyzing internal consistency and construct validity via 84 classroom observations, and (3) examining concurrent validity through correlations with student reading growth data. Results indicate high internal consistency (Cronbach's [alpha] [greater than or equal to] 0.81) and moderate, statistically significant correlations between framework implementation and the percentage of students demonstrating one year or more of reading growth (r = 0.42-0.68, p < 0.001). These findings suggest the RIGOR Walk framework is a reliable and valid tool for identifying and fostering rigorous, equitable, and high-impact instructional practices. Implications for broader content-area applications and longitudinal consistency of implementation are discussed.