I don't think it is totally accurate but would it give you a ballpark number if you try a DORA exam? It's about $15 from
www.homeschoolbuyersco-op.org more if you purchase it from the company. It might give you a reasonable idea of where his reading level might be. They changed things lately but if you finish the test and then go into reports you can get the comparisons for Lexile, DRA, and others. I don't agree with all the scores, my children take them regularly for state records, but they are usually reasonably close.
https://www.homeschoolbuyersco-op.org/index.php?option=com_hsbc_epp_order&Itemid=952
