<sigh> Yes Cathy, unfortunately this is typical second grade curriculum. Schools typically do not start multiplication until 3rd grade, and may start the beginnings of division by the end of 3rd.
Your little boy sounds very much like my son, who is now 8. DS understood multiplication and division before kindergarten, and has been reading advanced books since 1st grade. I know how you feel. It is a very hard call on what to do next. You can teach them material at home after school, in order to keep the love of learning alive. But that just makes the gap between what they know and what the other kids know even greater, and leads to increased boredom at school. You can advocate that they be accelerated again, in order to reach more challenging material. But I can say from experience that even with multiply grade skips, the material in the classroom just moves at too slow a pace for these kids.
The only thing that I can suggest from our experience, and this probably depends on the personality of the kid in question, is that our son can handle some non-challenging work at school as long as there is one (or two) areas where he is challenged. For instance, DS does not seem to mind that they just spent maybe 8 weeks reading a book that he read several years ago. Somehow he doesn't get frustrated with primitive reading assignments, as long as he can read more challenging material at home. However, DS has less patience with non-challenging math and science assignments, since they are subjects that he lives and breathes for.
So our compromise has been a whole grade acceleration, and then subject acceleration in math and science. This lets him stay with a good group of social buddies who are about 2 years older than he is for over half of the day in his 4th grade class. I think of this as his base camp. He is then challenged in the two areas that are most important to him by subject acceleration. This strategy seems to be working for the moment. <keeping our collective fingers crossed>. But even being 8 years old and in a 7th grade science class, we find that the pace of the new material is slow. But... it is way better than being stuck back in 4th grade science!
I don't know if this helps, or if the lack of a perfect solution is just plain depressing! But we are making due with a patchwork kludge. Our individual education plan (if we had one) should read, "Copious amounts of duct tape needed!"