For those who think learning English is as easy as just popping into a college and attending a course can I just run a scenario by you.
You're new to England, living with family in a community where everyone speaks your language. You can socialise and shop in your native native language.
You work sun up to sun down, then return home and cook, do the housework, look after the children and such.
You don't understand speak or read any English, so can't read any flyers that may come through your door, or posters, don't use things like libraries as you know you won't be able to access the facilities.
You stick to your small community because you can converse with them, they understand your culture, your faith.
So given the above, how do you ever find out that Leicester college run an ESOL course and where would you find out about it, and how would you enrol even if you had the number?
Add in that for some there will be cultural and religious reasons why they would be unable to attend or strongly discouraged from attending a mixed sex course.