A friend of mine found this sign in his neighborhood recently and at first glance we thought that it was an Engrish translation. I then went around my own neighborhood and discovered that we had the exact same sign in my own hood. That doesn't eliminate the possibility of it being a typo though and I am not picking on Thai people here. I think it is wonderful that they try to accommodate the English language all over the place even though we constitute a very small percentage of the overall population. There are other countries I have been to that have zero English in public and the fact that Thailand even tries is a huge help.
There is an ongoing joke among the expat community here in Thailand that Thai people are terrible drivers. No offense intended but this is mostly very true. When I was taking the test for my Thai diving license it was a joke. We had to prove almost zero skills other than being able to back into a parking spot and dodging a few cones that were so far apart from one another you could have driven a bus on that test course and still passed. The written test was in English and was basically nonsense. The questions were impossible to answer correctly because they didn't make sense.
One of the questions, verbatim, is this
The driver does not have the driving license. What's wrong?
It is a question asking what the penalty for driving without a license, which is a silly thing to have on a driving test anyway but there it is.
There is another question that apparently has been stricken from the test due to it being a global laughing point about something along the lines of "in a time of war, which vehicle has right of way on the road?" One of the answers was a tank, as if in a time of war tanks would be at intersections observing traffic laws.
Getting back to the sign in question, what is really going on here is that they are saying that the neighborhood cannot be used as a training ground for new drivers and this is actually something that people often will do with their girlfriends or whoever it is that they are attempting to teach how to drive. Although I didn't pay much attention to it at the time, I believe that almost every supermarket or shopping mall has this sign as well because those would be popular and rather safe areas to practice driving as well.
I asked a Thai friend of mine if the Thai script actually says that it it not allowed to teach driving in this location and that is precisely what it says. We all just found it amusing because since Thais are kind of known for not being great drivers, the notion that the government would be discouraging them from ever practicing was kind of amusing.
As always I want to remind everyone that I am not making fun of Thai people or Thailand. I love them both and yes, there are terrible drivers from all countries, not just this one.