If she was tested at four and is in K right now, the last testing was, what, about a year ago? I wouldn't retest at this point with the last test being so recent and even though you think that the # was off unless there was some really good reason.
A few thoughts come to mind:
1) How gifted is your older child and how does your kindergartener compare in terms of functioning? Do you have some reason to believe that your dd is more gifted than the older one?
2) If you have such a huge # of kids in GT in your school, do you think that it is a problem with overidentification or do you think that there are truly a lot of gifted kids there?
If it is the latter, might she be okay without significant acceleration (i.e. - might there be enough peers for her in her school)? Even though I have a grade accelerated kid, I would not assume that all gifted kids need acceleration and we would not have jumped to that choice had there been other options that might have met her needs.
