How can I download iTunes U videos faster? I want to download the videos from iTunes U, such as iPad and iPhone Application Development.

Lectures of previous semesters were on YouTube, so those of us with slow Internet connections could download/watch them without having to wait too long. But the latest videos are only in iTunes and seem to be, high quality, large files only. They take too long to download. 

Is there a way to download these videos faster, or download lower quality versions just like YouTube?

This isn't exactly a MacOS question, rather it is related to iTunes. I am asking the question in this site, because I can't find any solution in the internet.
I had the same issue. If u use Wi-Fi for Internet access, try using a different Wi-Fi network when downloading or restart your Wi-Fi router. Try using an ethernet cable for wired Internet access instead of using Wi-Fi. 
Also check for updates for your computer or for any security software you may have.