@JaneyLim88 If you are open to private 1-1 tuition rather than classes, I would recommend Frankie Cheah. He is a former MOE teacher turned tutor who has > 30 years experience. He has really helped my daughter develop the interest in science, and I am glad after 3 years of lessons with him, my daughter was able to get a AL1 in the subject (from a mid 60s when she started tuition with him in P4) !. Attached is one of her grades for a term paper last year before her PSLE.

Since you are looking for a teacher who usually teaches at the North east area, someone you can consider. I m just sharing since I got to know him from KSP forums, so paying it forward to fellow parents who are seeking help for their children in science. You can contact him at 81393075 for more information.