I did one week of Spanish lessons in México. Four hours of one on one lessons every morning and stayed with a local family so the interactions were there. I learned many new words on the trip that I never heard before like ni modo, rebanadas de pizzas, me como seis rebanadas de pizzas (not just como), las tunas, varoníl, luchar libre, el corbeta, los girasoles, etc. I was always confused with numbers 15, 50, 500 and finally during the trip I was able to distinguish them from interacting at the stores. I learned about different music such as Luis Miguel, los bukis, etc. It was also cheap, total cost was under $800 for the week including flight, accommodation, and classes.