Hi Claire! That is indeed a good idea. My former teacher Ken recommended the JQuery library and Ruby on Rails as great resources. I think they are wonderful too. This is meant as a general recommendation for a wide audience though, so make sure to peruse through Github repositories from some of your favorite developers to find examples specific to what you are working on and studying.
If you are just learning web development, I might actually recommend holding off on large open source libraries and looking at smaller repositories, programs, and algorithms instead. Larger projects are a great place to look once you have basic knowledge of a programming language and can hack together simple websites and programs without following a tutorial step-by-step but may not be hugely beneficial prior to that. The timeframe to get there can be anywhere from a month to a year depending on the time you have available, previous related knowledge, persistence, and curiosity.
Enjoy your learning and keep coding!