Academic here -- this brings up something that I always like to spread the word about: Contrary to some apparently common perceptions, grad school, especially in the sciences, generally pays you rather than the other way around.
Things like professional masters degrees (incl. some engineering degrees) are likely to cost money, but in the sciences both MS and PhD should be fully funded at reputable universities -- either through TAing, your advisers grants, or if you're lucky, fellowships.
Things like professional masters degrees (incl. some engineering degrees) are likely to cost money, but in the sciences both MS and PhD should be fully funded at reputable universities -- either through TAing, your advisers grants, or if you're lucky, fellowships.