Sources of funds can come from US universities, private foundations, US government agencies, civic organizations, private companies, etc. Scholarships - Based on academic merit. Generally require no repayment obligations. They usually cover full or partial tuition. Fellowships - Based on academic merit and generally have no teaching or research obligations.
Fellowships usually cover tuition plus cash stipend.
Grants - Generally based on financial need and merit with no work or research obligations. Teaching Assistantships - Awards are based on academic qualifications. They usually require a student to work 15 to 20 hours per week in such areas as lecturing, grading papers, supervising laboratory classes, etc. Students are usually paid a salary or stipend. Additional tuition waivers are sometimes included.