The i-Ready Placement Tables The primary function and purpose of the i-Ready Diagnostic assessments are to make appropriate instructional recommendations and placement decisions for students performing at different levels from Grades K–12. One important way this is done is through the Diagnostic’s grade-level placements. Once a student completes an assessment, their overall and domain-level scores are calculated based on the difficulty levels of the items the student received. 

The overall score takes into account all the items the student saw, whereas the domain-level scores consider only the items within a given domain. This information is then compared to the placement tables to obtain a placement. Diagnostic placement levels provide an indication of a student’s performance based on grade level. These levels are based on specific scale score ranges for each chronological grade (i.e., the grade in which the student is currently enrolled). 

Placement levels in i-Ready are criterion referenced, reflecting what students are expected to know at each grade level and in each content area. The standard setting used to set these scores involved more than 100 teachers and followed a research-based methodology recommended by technical advisors. These placement levels provide a standardized way of describing student performance. With these placements, educators can maintain a consistent perspective on placement throughout the school year and better see and understand movement between placements.

Read more information here - Scaled Score Placement Table