Scratch

Have you seen the "Language" button?

The blocks themselves are already translated into 13 different languages, including Spanish.  I would admit that the learning materials and some other parts of the user interface (such as the "New", "Open" and "Save" buttons) could use some multi-lingual support in addition to the blocks, so I would say that the multi-lingual support is still incomplete.

Once you have set the language, that setting is preserved each time you close and restart Scratch.  And unlike other programming environments, even the imported scratch files designed by other Scratch users also have their blocks translated to the target language.  This appears to be a huge strength for the concepts of Scratch programming in other languages.

Try it out.