Seekinginfo ... that's almost criminal, that salary. As someone who is aslo supporting a young family, I can't imagine trying to do it on 3700 a month, even in a relatively cheap place. If your husband is doing the stay at home dad thing for now I strongly recommend you guys move to either a bigger city, with better salaries, or you start looking at private schools. You could, I suppose, go to another university and get a similar salary and try and pick up privates on the side, but with a baby to support I'd be much more comfortable with a higher salary. Universities are good for people who are new to China, people who only have themselves to worry about, people with alternate sources of income, and people willing to work extra hours outside to pick up the slack. Trying to support your whole family on a university salary is just unneccesarily rough, imo.
Try the big, east coast cities, or Beijing. It seems like the bunch in Suzhou does pretty well for themselves, and I have friends making good money in Shanghai, Xiamen, and Guangzhou. I make over 10K RMB a month in Beijing, work 16 hours a week, and have my apartment covered by the school. Beijing is more expensive but you will make much, much more to make up for it. I am sure that even if you want to stay in Zhengzhou there are probably private schools, training centers, that will pay you at least 5000RMB a month.