Recommend great Spanish Immersion Summer Program for HS Student?

Hi all,

Can anyone recommend a 2-4 week summer Spanish immersion program that your kid loved?  Prefer Mexico or Central/South America to Spain as we live in Asia and spend summers in CA -- though a great program in Spain would certainly be worth hearing about.  It'd also be great if it had a volunteering/work component and not be wildly expensive.  Too much to ask?

Many thanks for sharing.