We've been there. Here's my take: With reading MAP, your child will grow by reading independently to a point. At some point, they NEED instruction at a higher level to grow. A winter test would have been helpful. Keep in mind, too, though, that at higher RIT scores, it IS true that growth can slow.

I have one DC in a high 99% that failed to grow in a subject altogether this year. This IS concerning, IMO, particularly because the child opined during the year that (s)/he was not learning anything new in this subject.

With kiddos in the 99th percentile, you need to almost ignore the percentiles. The more important question is: Did the RIT score grow? The child mentioned above is STILL in the 99th percentile (but won't be if this continues), but the RIT score is not moving.