Experience has shown that there is no relationship between being a good student and being a successful entrepreneur. Academic smartness does not guarantee success in business or life generally because the attributes of entrepreneurship are not taught in schools.
When I was in third year in school, we did a course called "entrepreneurship",it was still the same "cram and pour syndrome". There was no serious pratical skills attach to the course that could develop our entrepreneurship skills, except for those that have the passion or mindset to become a giant entrepreneur, who took extra effort and time to acquire personal skills.
Research have shown that if graduates decide to go into business for themselves, the straight "A" students may not necessary have any advantage over others, so don't be intimidated by your grades.
Many people don't know if they have these naturally endowed altributes until they take that small step that may result in a giant leap to become a successful entrepreneur.
Perhaps the question agitating your minds, if I may guess correctly, will be how do I become self employed after obtaining my first class, second class uppper, second class lower, third class or even ordinary pass certificate.
I ventured into business in my first year in school, it wasn't easy for me initially but after some time, it began to fluorish and make waves. This made me independent and employer of labours till date. I still graduated with a second class upper. So its all about time management and focus... Think about something and start, even if its small today, it can become big tomorrow. Government has failed hence can't employ everybody. The labour market is crowded and the "white collar jobs are very few". Don't let you academic grades or certificate intimidate or hinder you... The potentials might just be there. Its a continuous drop of water that makes an ocean... You can do it.

Well said. What a way to start tuesday morning.