We live in Ohio. Our school district is not really in favor of grade level advancement, but through the state,each system has to have procedures in place for identifying gifted students and different types of services they offer. In my district, if a child scores above the 95th %ile on a group administered achievement test they can qualify for enrichment starting in 4th grade or subject acceleration. The problem we are having is that my daughter was above the 95% in all areas. She is accelerated for 3/4ths of her day. She could enroll as a 3rd grader next year..and go to 4th but what happens in 5th grade-she can't access the 6th grade curriculum b/c they are in middle school. If she is succeeding in the next grade without any problems, then the system will have a psychologist do a full scale IQ and achievement test and give their recommendations on whether or not she would be successful. And then the WAP team makes the final decision from there.
I don't know what other states are like, I just know my district does not advocate grade skipping..but if you know the policies and have done the research, you can have access to anything. But they don't advertise it :-)
Thank you for all of your advice.