This set of Chrome Extensions will focus on those tools that are helpful when a teacher is busy grading online documents and other activities. Each of these can help in this process which was been indicated by others as being a challenge with the switch to a more blended environment.
1. Split Screen
Allows you to open two, or more, windows at once and have them side by side. You can open your grade book on one side and have the student work on the other. You can have email open while you are looking over a document or video that the student created. Makes it easy to have multiple things open on the one screen while you are trying to work.

Have a floating tab over your browser so you can keep one window open at all times. You can have your grade book or email open, floating above the other browser, while you view examples of student work.
Helps keep a 25 minute work period followed by a 5 minute free period while grading or doing other work. Keeps you from being distracted by other sites and keeps you from spending too much time working without a break. Good reminder to take a break every now and then so you do not get burned out.
4. dotEPUB
This extension will easily create an ebook from a site you are on. You could easily turn a resource into an easy to read epub book which can be viewed on any ereader. Save that site so you can easily read it on your Kindle or iPad later.
5. Window Tiler
Tile your open windows so that they all fit onto your screen without any overlap with the push of a button. If you have 2 open browser windows, it will put them side by side. If you have more, it will make it so they are as even as possible. You can drag a tab out of a window to make it into its own window.