Welcome!
I second everything indigo has said, especially out of level testing.
Most schools are wrapped up in NCLB law and putting all their resources in pushing their underperforming students to on-level standard. Great scores on out of level testing such as EXPLORE (too bad it is going away soon) and SCAT (through John Hopkins Center for Talented Youth) could be eye opener for the school administrators. If he is DYS level and get accepted to DYS program, DYS family consutant can also help you advocate at the school.
SCAT is available for 3rd graders and he can take it at the local prometric test center.
http://cty.jhu.edu/talent/testing/about/index.htmlGood luck!