Yes, schools have many opportunities for kids to learn a new language all through grade school. Schools have after school clubs, ESL (english second language) classes, spanish classes, french class, etc. There are no prerequisites and most of these programs are free of charge making these programs available to virtually everyone.
The majority of schools make learning the basics of a foreign language a requirement to successfully graduate, I think the majority of schools make sure that their students have a basic knowledge of the different languages and different cultures in the world, it's something very important to teach them and I think they do it sufficiently.
In the Midwest schools do nothing to promote bilingual knowledge and skills. The last I checked a foreign language credit wasn't even a requirement in high school, simply an elective. I believe we could definitely do more in this arena, at least here the Midwest where the topic is even discussed for the most the part.
Some schools require a certain, elementary level of second language learning later on in the school year, though this seems to be more of a method of college preparation than an actual earnest attempt at schools to better the language skills of students. It's introduced in high school in most cases, usually too late in life to make an impact.
Schools at this point when looking across the Untied States of America when comparing to the rest of the world are doing enough. Well some schools may be promoting the use of more than one language some are not doing so. This could be happening for a number of different reasons including funding.
Here in the UK we learnt French in our last year Primary School and in our first year at high school and German in our second year of high school. After that it was optional; which was where many people dropped out. Its not easy to learn a language but it should be encouraged with more enthusiasm. Its important that people learn another language as it encourages learning and multiculturalism.