Michael Duffy can help you use electronic resources in your class, by linking to them from Elearning or creating custom library guides (much like this one). If you need content for students to work with, please contact Mike at email@example.com.
A collection of orchestral excerpts in the public domain for brass, woodwinds, and strings, with embedded, time-stamped recordings from YouTube of the relevant excerpts played within the orchestral setting.
YouTube is a source of many, many streaming audio (as well as video) recordings. If you want to limit your search to recordings that are authorized by the record labels, and therefore both legally streamed and likely to remain available, add the string "Provided to YouTube" to your search. For example, if you want to find recordings from record labels on YouTube of Mozart's clarinet concerto, you might enter the following string into a YouTube search: mozart clarinet concerto "provided to youtube". See the example below.