Was reading the only thing they assessed? That seems foolish! I can't imagine that ability to read is the only thing a school should need to know when ascertaining who is ready to start K.

Like inky, I'd suggest seeing if they'd take private assessment results and get a more comprehensive assessment if so.

Are there any private schools that would take him early and do you want to homeschool or is it just seeming like the only alternative? Would they reassess when he is age ready to start K and consider skipping K and putting him directly into 1st at that point?