These are all things I have done for decades, I was mentored when I started teaching by the best. I do see many intructors making many mistakes because this school has no training/indoctrination program for new instructors, I would suggest the two courses mandatory training prior to anyone teaching a class.

Generally a person is given an ipad and shown their room and then they're on their own and without guidance they make the cardinal mistake of being their students buddy. They let the students call them by first name, they give their home phone and/or cell phone and tell them they will do whatever so they pass the course. They just opened the door to constant drama and assignments not done on time. Your name should be Mr/Mrs/Ms/Miss and your contact is your WORK email and school phone number and inform them of the hours and days they can expect a response.

You have to maintain a sense of leadership and due dates, just like at work, you're not the buddy, friend, mom or whatever, you're the boss, the instructor, the employer, the manager and you need things done on time. Once you give them the answers, pass them, cater to them you've lost, you'll never regain control and they will continue to be late and absent especially if you allow them to make up all the work after the class is over. There are instances where they really have a valid reason for missing one assignment. 

If, for valid reasons they cannot stay with the class schedule they need to take a LOA, get their life in order and return. You can't have students always handing in things late, not participating, not attending, and then let them hand everything in on the last day or after the class is over, you'll never break the cycle and then others will do it.  

You're not helping them and you're creating madness and drama for yourself, remember what the course said ---They will push you as far as they can to make exceptions for them. Remind them that people hire them to perform a service or produce a product. When they are out in the field, their customers and/or employers won't accept their late or incomplete work.