Ahhh. I think I understand the difference between STEP, SCAT, and the WJ III. And your explanation of the GEs makes sense too. DH and I are used to thinking in terms of uncertainties and error bars on numbers and graphs. I think that when the grade level projections become extended out beyond multiple grade levels, then the uncertainty of those projections begins to swamp the useful data. That is what we saw when we looked at the grade equivalent for DS's science score.

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The scholastic Powers That Be don't like to acknowledge what a range the "general public" has in its ability level, and most are still holding to the pipe dream that all children can learn equally.

I also like your insight in to the scholastic Powers that Be. It explains a lot. Really.

Mom to DS12 and DD3