The Illinois Assessment of Readiness (IAR) is the annual standardized test administered to Illinois students in grades 3 through 8. Covering both English Language Arts and Math, the IAR replaced PARCC in the 2018-19 school year and is now Illinois's primary accountability measure under ESSA. This guide covers everything you need to know about IAR test formats, scoring levels, grade expectations, and the best way to prepare with PARCC practice tests and released IAR materials.
The Illinois Assessment of Readiness (IAR) is the state-mandated standardized assessment for Illinois public school students in grades 3 through 8. Administered every spring, it measures student proficiency in English Language Arts (ELA) and Mathematics and is the cornerstone of Illinois's school accountability system under the federal Every Student Succeeds Act (ESSA).
The IAR is administered on computers in Illinois public schools, typically during a testing window that runs from March through April. Results are used by educators, parents, and state officials to gauge student progress, identify instructional gaps, and evaluate school performance across the state.
The IAR replaced the PARCC assessment beginning in the 2018-19 school year. While Illinois had administered PARCC since 2014-15, the state transitioned to the IAR as a standalone assessment with Illinois-specific scoring benchmarks and a reduced testing footprint. Key differences include:
Because the content framework is nearly identical, released PARCC items and practice tests are among the most effective preparation tools available for the IAR.
On the IAR, students must reach Level 4 (Met) or Level 5 (Exceeded) to be considered proficient. Levels 1 through 3 indicate varying degrees of below-grade-level performance and are used by schools to target instructional interventions.
Proficiency rates are publicly reported at the school, district, and state level and factor into Illinois's ESSA accountability ratings. Schools with consistently low proficiency rates may be identified for additional state support.
The Illinois State Board of Education (ISBE) releases sample IAR items and practice materials each year. Combined with released PARCC items — which share the same content framework — these are the most accurate preparation resources available for students in grades 3-8.
The IAR uses a five-level performance scale. Levels 4 and 5 are considered proficient, reflecting grade-level mastery of Illinois academic standards:
Illinois reports IAR proficiency rates publicly at the school, district, and state levels. These results feed directly into ESSA accountability metrics and influence decisions about additional school support and resource allocation.
IAR results serve multiple purposes in Illinois's education system. At the student level, scores help teachers identify which skills require additional instruction and which students may need enrichment or remediation. At the school level, proficiency rates are a key component of the Illinois Report Card, which parents and community members use to evaluate school performance.
At the state level, IAR data is submitted to the federal government as part of Illinois's ESSA plan and is used to identify schools that are not meeting performance targets. These schools may be designated for Comprehensive Support and Improvement (CSI) or Targeted Support and Improvement (TSI) status, which comes with additional monitoring and required improvement planning.
For students transitioning from elementary to middle school or approaching high school, IAR scores can also inform course placement decisions, particularly in mathematics, where performance may influence whether a student is placed in accelerated coursework.
Students in other states with similar assessments — such as the NJSLA practice test used in New Jersey — face comparable computer-based state assessments aligned to college-and-career-ready standards, making cross-state practice materials a useful supplemental resource.