I'd agree that the MAP scores especially the comparative RIT charts can sometimes inflate the grade level equivalent. In our district where a 250 on the MAP score in fifth grade is used to determine entry to Algebra I in sixth, the cohort has had a mixed record the next year. There are some kids who are ready (and in fact often are learning Algebra outside school) in fourth and fifth grades. Others struggle in class. All of which to say I think there are better algebra readiness assessments out there if that's the question you need answered.
