How about.. U.K and Japan both decided creating a school in Japan that supported tolerance, with the added bonus of learning the culture of the other in the process. Japanese students would be taught English from Kindergarten to 8th grade (unless they already knew it), and then the English students would learn Japanese from Kindergarten to 8th grade. This would help students talk to others normally with ease and without confusion. Throughout that time they would also learn about the culture of each other. The Japanese students would learn English culture, and the English students Japanese culture. Of course, they would still be learning math, science, and all the other subjects. (Oh, I forgot to mention they would learn how to write in the other's language as well.)
During the High School years it would be far more relaxed and easygoing, but there would be celebrations of holidays for each culture, every student Freshman to Senior included. There would also still be the once a week teaching of the languages, though this class would take up all day. Just once a week though!
I hope I explained that good enough.....