We have love Highland View for our DS who is an above grade level learner. The K-2 classes are small, like 15-18 per class. So, there is more attention from the teachers. There are reading, math and spelling groups within the classroom, and some advanced readers from other classes come to DS's class for reading group There is combined 4/5 class this year. We are not familiar with the details of it, but I heard it was a way to keep class size down an also provide some challenge opportunity for the 4th graders in the class. I have neighbors who sent one child to the HGC at another school, but decided to not even apply for their younger child because they felt he was happy and challenged enough at Highland View.
I think that any concerns about challenge at the school are general issues with 2.0.