How do you get back into studying when you've been slacking for so long?

Answer 1

You mean you want to re-enter school or you want to change attitude?

If it is re-enter school, talk to the school itself.

If it is attitude you need to do some reassociation. Basically you have pain and pleasure. List all the reasons you want to do well. And think of how this will benifit you in the long term, how you, your family and kids would be better off. Associate learning, even when you are frustrated to enjoyment and wonderment. Each time you get frustrated just think of how interesting this is that you cant do this now but will be able to in a moment. Hope this helps.