Final answer:
Progress monitoring is essential to effectively implement RTI and determine if additional intervention is needed.
Step-by-step explanation:
The process that is essential to effectively implement RTI and measure students' response to interventions is progress monitoring.
Progress monitoring involves regularly assessing students' performance and progress in order to determine if additional intervention is needed. This can be done through measures such as standardized tests, benchmark assessments, or teacher-made assessments.
By monitoring students' progress, educators can make data-driven decisions about the effectiveness of interventions and adjust instruction accordingly to support students' learning and growth.