What is the best way to embed content so that it is available at the top of the page at all times?

Create an update in any course and select "annoucement" after you post. It will then stay at the top of the Updates page in your course until you add a new annoucement.

The only option (and it doesn't apply to all things you would embed) is to put an item in "Updates" then before you post, check the box immediately beside the "post". When you hover over it, it has a bell. By checking this, it stays at the top of both the Updates queue and the Materials page until you close it. You have to check the box before posting, because you don't get the opportunity after. (I've tried.)