A native Spanish speaker in the U.S. can learn English for free through U.S.A Learns, a free online course offered by the U.S. Department of Education. He can also look for local resources through the U.S. Citizenship and Immigration Services or a local library branch.
One resource for learning English on the Web is The Department of Education, which runs the U.S.A. Learns website and provides English language courses online for free. The website also includes resources for reading, writing and speaking skills.
To expand language skills beyond the basics, it can help to take an English course in person and interact with classmates and an instructor. The USCIS offers a wealth of information for language and citizenship classes. Local social service providers and community organizations usually offer the classes themselves, but English students can find courses in their area through the USCIS website.
Many library branches also provide language and literacy classes, which can be a good option for people who do not have access to USCIS funded courses. English students can find local libraries through the Institute of Museum and Library Services Public Library Survey and review available courses at their local branches. Classes are often free or low in cost.