Need job search advice from those with kids

I need some help. I have 4 children. My youngest is 3 months old. I am a new grad LPN looking for a job. Money is very tight right now, so my husband is working tw0s jobs right now. Thus, he is hardly ever home, and still we arent even able to make ends meet. Thus, I REALLY need to get a job. Only problem is, I have no one to help me with my kids. I keep reading that the best way to get a job is to go apply in person, but if I do that I will have at least two kids in tow (my older two are in school 4th grade and K), and I doubt that looks very professional, and what if they want to give me an interview on the spot? There are hardly any times I can go to an interview, either, so I dont know what to do. My husband is home at night on Mondays and Wednesdays and Sundays from 6 pm on, but I doubt facilities would have anyone to talk to working then. The best I could do would be walk in and get an application and fill out then, just have no one to talk to at the moment. Is it ok to fill out an application and call a few days later to see if anyone looked at it? Is it ok to call a facility first to see if they are hiring, or better to just go in? I have no problem with calling them and asking and then going in to fill out an ap if they are hiring, but I dont know if it is unprofessional to call and ask. Please help! Any advice will be much appreciated.
~Missy