If you are providing links to external materials, such as videos, PowerPoint, handouts, podcasts, and so forth, make sure in advance you have the rights to post these materials (a good rule of thumb for using other folks' material is "please and thank you are the golden rules").
If they're your own documents and materials, consider clarifying your licensing with a Creative Commons share-and-share-alike license.
Note: if you are producing this material for your organization, you may want to check with your higher-ups to make sure you may share this material and ask what licensing rules apply.
CC licenses are very easy and quick to apply for (even fun – you get to twirl a couple of knobs in the process!). You do have some choices for the licenses. Generally, the broader the better is a good idea, such as this attribution, commercial-use, share-and-share-alike license.
When you have applied for your license (which should take less than a minute), then paste your license on your document, save it, and that's it.
Note that material that is explicitly licensed under Creative Commons as "share and share alike" can be used without informing the source, and because this is the Evergreen wiki, you can also assume it's fair to link to material licensed for noncommercial use. You don't have to advise people who asked for attribution that you're linking to their resources – but it's certainly nice to let them know, and be sure to attribute their resource in the manner they requested.