MAP testing is progress testing. Will they retest him in the spring? If he is making good, steady progress, he is likely learning something new. If he is NOT...he may need more challenge/new content to make further progress.

What I have learned is that the name of the class they place my DYS in is meaningless. It can be called "Gifted Honors AP Triple-Accelerated Basketweaving" (yes, this is a bit tongue-in-cheek), but if my child's progress isn't there when he/she takes the basketweaving spring MAP (pick your MAP subject), he/she is probably not learning anything new. This is particularly true if the child is also coming home telling me they "keep doing things over and over that I already know," or "everything is the same as what we did last year" and/or "I am sooooo bored in basketweaving class" etc. So really, it is how much they are learning, no matter the title of the class, that is key. Most schools do not pay enough attention to the students at the top, particularly if they are outliers (in fact, many don't even grasp the concept of outliers). That being said, you know the content of the course your older DS is taking and you seem to think that your younger DS is well-suited for it. Could you ask them to allow your son to try the class for 4-6 weeks to see if it is a good fit?