Goguardian allows you to create different Filtering policies based on your (OU) structure. For instance, you could block youtube.com for specific (OU) while leaving the site open to other (OU). Below is a link to an article written by GoGuardian.
Creating a new settings profile
If you are a visual learner, a link to the video tutorial on how to create a new profile for your Organization Unit (OU) is below.