Without looking at them, I can't say for sure, but they sound like molloscum contagiosum. Google that and you'll find a bunch of information.
My daughter had them - they start out like tiny red bumps, usually very hard to the touch. Then a white head develops in the middle and eventually they erupt, like a pimple. They are extremely contagious and are easily passed from one child to another.
Swimming pools and daycares are the most common places for the virus to be passed around because the virus can live for some time in water as well as on hard surfaces.
To keep your other children from catching them, you would want to wash her bedding and her cloths in hot water and wash your hands after touching the bumps. Tell her not to touch them, if that's possible, and have her wash her hands frequently. Put bandaids on the ones that have erupted or are about to erupt. And don't bathe your children together.
This is what my pediatrician told me: While ugly, they are not harmful. They are related to the same virus that causes warts. Most children develop a natural immunity to them in 1 to 2 years of being exposed to them. Adults don't get them because they have already developed the immunity. The only adults that do get them have a compromised immune system.
There was a good thread about molloscom 6 or more months ago on mamasource - a lot of moms had great advice about how to care for them. One mom said she used hydrogen peroxide with success. I can't remember all the other responses, but you might want to do a search and see what you find.
Of course, my answer assumes your daughter has molloscom! I'm not a doctor, so please don't just take my word on this! Seeing a doctor is always the best thing to do - although I truly do understand the challenges of no insurance. Perhaps another mom will have advice about how your could find low-cost medical care for your LO.
Best of luck.