If you are studying either Portuguese or Quechua, you may be eligible to apply for United States Department of Education FLAS fellowships to support language study.
These grants are administered by the Center for Latin American Studies and usually have a February deadline.
Consult their website for more information. Undergraduates can apply for summer tuition up to $5,000, plus a $2,500 stipend, to support taking a FLAS-approved intensive language course.