Is this why Negroes just can't act right?

I supervise 5 employees. And I've struggled (internally and externally) about what to do with them. The problem: They all are un-disciplined and behave unprofessionally. I've rung my hands and held my forehead. I've emplored my boss to help me help them.

I spend 90% of my work day micromanaging them. (And I hate micromananging. And why should I have consistly tell Adults what to do all of the time?) It goes like this:
Stop that.
Put your cell phone away.
Don't curse.
Don't call each other that.
Don't use the N-word.
Why didn't you come to work yesterday.
Keep up with the group.
Where are you?
Where did you go?
Wake up.
And let's not forget the constant need to remind them what were doing each and every minute of each work day. I give them calendars, I tell them to take notes. And still they seem lost.

I'm supposed to supervise them in doing environmental remediation work and preparing them to give environmental education lessons to groups. I am so far behind schedule. They simply aren't ready. They're just too unprofessional and potty-mouthed to put before a group of children, seniors, heck anybody. And yes, I and my agency have presented professional development seminars, we've discussed the do's and don'ts, etc. But nothing has changed.
And I keep coming up the the same answer. They don't care enough to want to perform their duties better.

Straw breaking the camel's back incident:

Last week, my employees and I all were participating in a training program. The program covered topics and principles that are necessary for one of our essential functions: Provide environmental education lessons to general audiences and school groups. On day one, 3 of my employees were uninvolved. Even after a stern talking to, they remarked: "This is boring. These white people are boring. What are they talking about? Why are we here?" No matter how many times and ways I explained that this training will equip them with the skills necessary to present quality programming to people, they still didn't get it or rather they didn't care to get it.

I was so frustrated I decided that "These Negroes just don't want to learn!"

By the third day of the 4 day training, 2 of them had walked out of the training remarking how they didn't need the certification or care to have it.

So Sunday, I'm reading an issue of Science magazine and come across this article: Preschool Program Improves Cognitive Control. Cognitive control (or executive function as they call it) are those "soft" skills that make earnest learning possible. In other words, it's the ability to inhibit yourself, resist distractions or acting out in class, it's the foundation of basic memory and recall -so that you don't ask your teacher 10x "what did you say?", and it's your ability to deal with minor changes or adjust to lessons learned in different contexts. Real basic right?

Then the light bulb went off. These are all of the issues I'm dealing with DAILY with my employees. As the old folks use to say "They have no home training or common sense." They are off the chain. They are undisciplined. They have poor COGNITIVE CONTROL.