Hello! Thank you for using Alloprof! :)
Math CST is the basic mathematics course, whereas
SN is the advanced one.
Science ST is the basic course, and
SE or STE are the advanced ones. In order to take math SN and chemistry in sec 5, you
need to complete both advanced courses in sec 4 (Math SN and Science SE/Science STE or EST). If you are currently taking Math CST and Science ST, you may need to talk to your school advisor in order to try to see if you can join the advanced classes. If not,
some schools offer summer school between sec 4 and sec5 allowing you to acquire the necessary knowledge to take SN and chemistry. We call them «bridge courses».
*** These courses may or may not be offered at your school. You need to contact your school board or your school district in order to prevent any bad surprises! :)
Hope that answers your questions! We wish you the best of luck! :)
Sarah G