For DYS you need one of the following: 1) IQ & Achievement testing; 2) IQ testing & portfolio or 3) Achievement testing & portfolio.

The specific testing requirments are found here.

http://www.davidsongifted.org/young...holars___Qualification_Criteria_384.aspx

Not sure if you are applying for DYS or the Davidson Academy (DA). DA has similar requirements as above and those can be found at

http://www.davidsonacademy.unr.edu/Articles.aspx?ArticleID=144&NavID=1_33

In terms of Chicago area, there are several people on this board who are from that area and have recommended or talked about testing. I suggest searching Chicago in the search feature that should bring up a place to start for you.