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How strong are your math skills? If you've learned at least algebra, I might suggest SICP and HtDP together, the reason being is:
Both are self contained. You can do everything in it without needing an internet connection
SICP is comprehensive, and HtDP is a bit easier of a learning curve.
SICP is free as an ebook for Kindle/Android/iPad, as a mobi file. HtDP is available online (free) or in print ($).
There are Scheme interpreters for both Android and iPad.
Which means that if you can get a cheap 10" Android and load it with software and books in a library, you can literally learn to program anywhere you won't get caught.
Both SICP and HtDP are the basis of many freshman level University courses. The skills you learn from them will be applicable to and other languages you learn later.
Best of luck.