I think you are asking for test prep for the entrance exam for the science and tech program - that would be the PSAT 8/9 test. Test prep for that is usually at the beginning of the school year because the test is in October (isn't it?).
If you live near University Park, you might want to try to get into the test prep course that a University Park elementary school teacher has taught for years on her own, not through the school. In September, call the UP elementary school secretary and ask her for the name of the school parent who is organizing it or the name of the teacher teaching it or the name of the PTSA president who might be able to connect you to the right person. If the school secretary doesn't doesn't know, don't give up. It can take a few phone calls and lots of kindness.
But because the county switched from their own test to the PSAT 8/9 a few years ago, you can really go anywhere for PSAT prep.
Individual or group classes -
http://www.innovativetestprep.com/
Also, I've had good luck finding tutors on the county on
https://www.wyzant.com/
I wouldn't do Khan Academy for PSAT 8/9 prep, though. It's geared toward PSAT/NMSQT (National Merit Scholar Qualifying Test) and SAT.
https://khanacademy.zendesk.com/hc/en-us/articles/227182968-I-need-to-practice-for-the-PSAT-NMSQT-PSAT-8-9-or-PSAT-10-where-should-I-go-