Is there any way to find out a general breakdown of how %C (percent correct) scores map to national percentiles?
For the younger grades, like grade 1, I would expect that the 50% percentile for a test like this might actually fall well below answering 50% of the problems correct. Little kids are still learning how to follow instructions, stay on the correct question, fill in the bubble properly, etc., not to mention all the first-graders who come to public schools speaking predominantly a non-English language at home. I wouldn't be surprised if the 50% percentile actually scored about 35% correct on ITBS, but I have no way of knowing. Is there any way to know the historical mapping?
