Originally Posted by aculady
there are three ways to determine that an impairment interferes with achievement: comparison to age-peers, comparison to state achievement benchmarks, and comparison to the child's intellectual development (IQ).

do you have a citation for this? I'm curious because our state's RTI implementation document explicitly excludes the use of a discrepancy model (i.e. a discrepancy between IQ and achievement). In this respect, RTI seems to have made things worse for 2e kids in our state.