I would think if your son overall belongs in the grade level he is in then I would plan a lot of activities outside of school to allow him to explore his interest in science. We finally reached a point in all subjects but writing and that is why my DD9 only attends for ELA.
I haven't seen any in classroom differentiation in science in our district. The push just doesn't seem to be there in elementary school with so many kids struggling just to read and write. I was talking one day with a first and second grade teacher and they were discussing how much more they would love to do with science but just aren't able to with so many kids struggling in other subjects and the new pushes to make sure kids will test well. There has also been a new push with writing in our district that has pushed science back even more.
