Perhaps 20 years ago, we had "degree teachers" who were among the best students of their time, having read a degree from the two prestigious universities in Hong Kong, The University of Hong Kong, and The Chinese University of Hong Kong. The implications then were that they are well-versed in their matriculation and undergraduate studies, and they know the knowledge by heart, most of the time adequate to explain issues inside and outside the then-british curriculum to students.
For me, secondary science education was a great introduction to science and certainly what led me into clinical medicine and research. For those who believe in that you don't need much more than the curricular knowledge to teach science, I would give two simple phenomenon that I encourage your kids to ask their science teachers:
(1) Why is metallic mercury a liquid at room temperature and pressure, and
(2) Why does a mirror reflect light of most visible wavelength
The phenomenon in both questions are simple, and taught at perhaps primary school or junior forms, however, the ability to explain these to matriculation students (who, presumably, had the prerequisites) are certainly not found in most teachers I have personally met. If one has not heard of the answer before, it's readily derivable from basic principles in relativity and quantum mechanics taught at A-level Physics and Chemistry.
What this example illustrate, is that you need science teachers who knew much more than the mere curricular knowledge to teach, and to inspire students so that we won't miss a potential scientist in the future. If there should be a reason as to why we had less and less locally schooled scientists in the past 10 years, it probably had to do with the ability of teachers these days.