Unfortunately when we are at school, many of us do not take advantage of the education that we are being offered. You may find school boring or that a lot of what is being taught is irrelevant, but as you get older there are often times when you look back on experiences in school and realise that they have actually assisted you in work or in life in general.
Some people decide to return to education at an older age. This may because a certain qualification or degree is required to apply for a position in your chosen career. Often when people return to education by choice they seem to enjoy it more and do better than they may ever had done at school. This is because the pupil has had the time to decide what they want to do and is going to be choosing to study rather than forced to.