Some library schools probably offer this as a course of study. Mine did not. My library school required a self-created webpage portfolio at the end of the program. In order to create this portfolio, we had to code the webpage from scratch. There was not a lot of instruction in coding, and we were mostly left to our own devices. While I did learn some valuable information at the time, I couldn't code a webpage today if I tried.
And I do think that coding is a skill that is more and more useful for librarians. Librarians needs to be agile in their positions to remain relevant. We need to possess more skills than ever before and take on more responsibilities in a time of return-on-investment thinking in higher education and the seemingly constant cycle of reduced budgets.
Because my library school did not really teach me how to code, and I see at as a necessary skill for librarians, I decided to take advantage of one of the free massive open online courses or MOOCs to help me along.
There are also many other online courses for learning web design.
The beauty of this is that most of this information is free and open to anyone with the dedication to learn. And a certificate from these free courses may even be considered a legitimate alternative credential one day as more and more people earn certificates and show that they have the requisite skills.
The Census is event starting to track alternative credentials to gauge the education level of the American population. "The federal government for the first time has data on the 50 million U.S. adults who hold some form of educational credential that isn't a college degree."
The time has come to take advantage of free online learning.
Image info: http://commons.wikimedia.org/wiki/File:Html-source-code.png#filelinks