Work ethic results from the kids seeing the parents model it. When young kids want to join in and help the parents out, don't scold them, tell them how to do a better job. Let them help and have fun doing it. They will look forward to the family time that work gives them.
If they hate what they do - then chores won't give them a good work ethic - they will just try to sneak and do a lousy job, or skip the chores.
Think of them as part of the team and appreciate what they do.
Your biggest hassle will be peer pressure and drugs and booze. Be part of their life, know the details, and share it. Discipline doesn't make a parent. Sharing and appreciating does. Go the extra mile and they will meet you on it. - Mostly, your kids should smile when they see you - not duck for cover because you have a chore for them. Work along with them, talk, smile - and they will adopt your work ethic and manner.
Good luck.