It's hard to support a family on one income - I cannot imagine trying to also have a child with cancer. If the full need of a loan is contributed to medical costs, then you have done well on budgeting. If not, have you made a monthly budget? Are you figuring enough for groceries, health care, gas, clothing, etc. Collect all of your bills & receipts for one month. At the end of it, total up each category to see if it's what you've got budgeted. Eating out quickly adds up - even just going to Chick~fil~a and other cheap places. Does your husband make enough to meet the budget? If not, you might need to get some part-time work while the kids are in school or when you husband is home so you can avoid daycare costs. How much is he paying for benefits? Perhaps your part-time job will have better benefits. Since you'll be starting school in January, you might just consider picking up a temporary job for the holidays. I think Dillard’s pays $10-12 an hour. And Macy's at Penn Square had signs up yesterday that they were hiring for the holidays.
Okay moving on - You have several options. If it is for nursing school, then apply for financial aid like someone else recommended. While you are in school, your payments will be deferred and the interest rate is going to be reasonable. On some of the loans, the fed will help pay the interest that accrues on the loans while you're in school. Here's a link to the federal student loan site for all of the info.: http://www.fafsa.ed.gov/
If you just need cash in general, you could do something like Payday loans, but expect to pay out the nose in interest. Even the government thinks you will get the shaft if you utilize a payday loan and has come up with some alternatives. Here is a link to a very good article published by the FTC:
http://www.ftc.gov/bcp/conline/pubs/alerts/pdayalrt.shtm
Also, if you have a car that's got equity in it, sell it to get the cash out of it and keep part of it to buy a $2k used Honda which will run forever. If you have any equity in your house, considering trying to refinance it. This might be a good option because you will have a lot longer repay term which will keep your monthly payment low. If your credit is so bad that your lender won't approve you, you can look at using a mortgage broker. They are easier to finance through but expect to pay more and have higher fees, but still it is an option. Again, it depends on how much $ you need & for how long you need it. Depending on your answers, this could end up being more expensive than payday loan in the long run. Also, if either you or your hubby have a 401k, then you might be able to borrow against it. If you absolutely must, you can cash out a 401k - but you will get taxed out the rear.
Figure out how much money you need, and is this is a one time thing to get caught up, and then look at all of your options to see which one is going to be the least expensive. Look at savings accounts, a garage sale, putting unused items on Ebay to generate some cash.
Overall on paper, the best economical solution to benefit your family would be to get the holiday job. This involves no loans, paperwork, high interest rates and most importantly you are EARNING instead of BORROWING - which is really the ultimate solution. You need to bring money IN (income) instead of paying it OUT in the form of interest, etc. which puts you further and further behind. Borrowing just delays the inevitable - you lack income to pay cash for what you need or didn't expect (like an illness, job loss, etc.) and bringing money in is the only way you can break the cycle.
I know it's not easy and I hope you find a solution that works well for your family. Good luck!