I hope your child's teacher is keeping close track of the works he has done. If they're too easy, why don't they skip ahead and try something much harder without requiring a show of proficiency first, just to get a feel for where he's at? I think that if the montessori teacher thinks about it carefully, they ought to be able to come up with a plan.
What age/grade level is your child, and where do you think he's at (with math/reading)? Figuring out what he can do with math, for example, shouldn't really be that difficult, though I do understand what it's like to have a child who pretends not to know anything and who is afraid to try any work that might require him actually having to use his brain (due to both fear of failure and exertion of mental effort in an otherwise too-easy world).
DS7 is in second grade. We homeschooled the first semester of last year to "complete KG" and then he spent the second semester at the Montessori school completing first grade. He's in second grade now. I think they're having a hard time believing that the work is too easy because as soon as ds sees the assignment, he asks for help or says it's too hard. It's his way of procrastinating and avoiding doing the work. The teacher says that she's very open to the possibility that he's mastered the material, he isn't showing her that so she has no way of knowing for sure. I can see her dilemma.
I know he knows most of this work though. For example, the other day one of his works was to learn about "er," "or," and "ar." He had to write (not his favorite thing!) 10 "er" words, 10 "or" words, and 10 "ar" words. He didn't even have to generate the words. He just had to copy them. Maybe I'm off base, but ds is reading at a 6-8th grade reading level. That would lead me to conclude that he has mastered er, or, and ar, correct? That's just one example, but it's as if they're looking at each "work" in isolation rather than looking at the big picture.
Also, while he knows how to add and subtract well, he's not super fast with it. Because of this, he hasn't moved on to multiplication or division. When we were homeschooling he was doing long division, and that was a year ago. He hasn't done it once at Montessori. I think any school is going to have a tough time not going through linear steps, especially in math.
The school tells me they can be flexible with the pace of completing the works, and they even said ds can skip works if he can show them he knows the material. I just don't think they have a clear idea of how to have him do that. Also, I asked the teacher the other day if they were reviewing from last year, and she said yes. She also mentioned that because ds was only there for one semester he didn't complete all the works. Honestly, does he really need to complete all the works? She just said it's ok to skip them! Her heart is in the right place, and she really wants to help. I just think the whole Montessori philosophy, which works well for so many, is ingrained to such a degree it's hard to step outside the box.
Does he ever ask for specific works? Is he afraid to ask for some reason? Does he need a lot of direction? Different kids approach these things differently. How about his teacher - is s/he willing to demand more of him, or is she wedded to child-led work selection? I guess I'm trying to get at the root of the problem....
DS has particular works that he prefers and expresses an interest in those (specifically, "who am I: problem solving exercises and creative writing (only if he can choose the topic). I don't think he feels like he can ask for any works outside of his work plan. He is a very "rulesy" kind of kid. He may become extremely frustrated by the rules, but he's not a rule breaker. The teacher would be fine with demanding more of him. I think she's afraid that if she does, he'll have even more meltdowns. The problem is, in Montessori (at least at our school) demanding more means more writing. While his writing is good, it takes a decent amount of effort on his part. Interestingly, he can write forever when it's in his journal at home. That's when he can be creative. He does need direction. He has ADHD and tends to get off-task. I think he asks the teacher for help when he's having trouble staying on task (to me, this is a good compensatory strategy on his part). She interprets this as him having difficulty with the academic work.
As for the testing, I'm not sure what the difference is that you're asking about - the private school psych vs. a neuropsych - they ought to be able to do the same thing, though a neuropsych who specializes in gifted/twice exceptional kids may have more expertise in the test administration and analysis that would benefit your son (if the private school psych is more accustomed to "average" kids). If the cost is similar, I'd definitely go with the neuropsych.
I think neuropsych testing will be more thorough and looks at things from a more medical/cognitive perspective, while psychoeducational testing looks more at how learning impacts the child in the classroom only. At least this is my take on it. My problem is finding anyone who is well versed in testing 2e children. It would be easier to find someone to do the psychoeducational testing, but neuropsych is probably the way to go.
On a side note, a few minutes ago I received an email from ds's teacher with a list of topics he is studying. They all sound more advanced that what he describes to me. Hmmm....Not sure what to think about that.
Thanks for all of your advice.