there's entry requirements to various jc here http://jctuition.wordpress.com
Pls take note that GP is an extremely tough subject and you need to be good in English to score.
JC may be tougher than poly, just to caution you.
All the best.
For poly, if a student gets 2.1 points on the first and second semesters, there goes his or her chance to go into the local universities.
For JC, the students can fail all the tests and exams and provided he or she work very hard for the actual A level exam, he or she still has chances to go into the local universities.
Last minute work in JC will not work, unless the student is super brilliant and can learn concepts in a very short time.