There are many reasons why we don't have more successful entrepreneurs and our education system is not the cause of it. If you think schools create entrepreneurs then I am sorry to tell you don't understand business very well. You might as well ask why we don't have astronauts on the moon.
I don't think we are too stupid to start big businesses. More than anything, the lack of market size in my mind is a major contributor to the lack of global success in businesses. Also, general risk aversion of the population, which is more of a societal issue than a school issue. Other reasons too, lack of safety net, less developed capital markets, ..etc. As for notable inventions, we are actually pretty good research wise. See link below for our local univ's academic reputation is research cited.
http://www.usnews.com/education/wor...versities-statistics-and-operational-research
Why I think Singapore education is good? Well I am not an expert but I have two kids in the US education system and based on my comparison, they are about even. In addition to US schools, my kids also go to Japanese public schools for several months during the US summer breaks and I compared what was taught in the schools, same conclusions. Overall, Singapore is stronger in some areas and not as good in other. I also know several teachers who used to teach in Singapore and now teaches in the US, they thought highly of Singapore's education system. Are there better systems? Probably yes, but compare to public school systems elsewhere, I would say Singapore is pretty good. I am also sure you have seen global ranking and what not that confirms that same thing.