I read that teachers in SG cannot accept present that r 2 expensive. True? Is there a limit?

Teachers are civil servants and from what I know, there are indeed restrictions in terms of receiving gifts. But how expensive is expensive to you? If I were the teacher, even without the restrictions put in place, I'd still feel weird accepting extravagant gifts from parents especially in a professional setting. It's the thought that counts and it doesn't have to cause a bomb yeah.