We are at a magnet school with gifted services. Kai- your answer is exactly what I was looking for. I can only hope that the questions on the GT prep site were representative as far as difficulty and time goes - we had 7 minutes left at the end of the test and had spent time discussing many of the thought processes behind the questions while we completed the test.
The cutoff is aound 80 or 85% score on the CogAt if I remember correctly. The students with adequate scores take the ITBS a few weeks later and scores on that test determine eligibility for 4th and 5th grade gifted services for math and/or literacy.
