I teach second grade, and I use Evernote in SO many ways.
I only have one class, so I don't have to worry about 100 kids, --I started to utilize stacks. I have a stack of my class, with the student names in my "class" stack.
Since I teach 2nd grade, we use standards based grading. I scan so much work in, and Evernote is basically my grade book. I do this various ways---Whenever I scan work in (I use an Ipevo webcam or my iphone and the JotNot Pro app), it automatically goes to Evernote by using the import folder tool. This is great because I scan in work almost every day. The JotNot Pro is great when I have multiple pages that I want as 1 file.
Occasionally, I share a student folder with a parent or specialist if we are working together on a plan to help a student (eg. IEP, 504 plan)
Lesson plans-I have a "curriculum" stack, where I keep my subjects---many webclips and curriculum documents wind up there. Lot of times, I think of ideas for current or future lessons and they get sent here as well. Many times through the year, my kids are journaling, and I never was able to keep all my ideas in one place--now whenever I give a journal topic--I send it to "journaling".
Email--I love the way that I can send an email so that it goes to a specified folder---here is the link to do that -- email
Livescribe-wow- I use Livescribe pens in my classroom--I have a page for each student. Anytime I take a note, it updates my notes on that student. Instead of scanning, I can just have my student write on the paper for a quick assessment. (plus tons more ways...)
I use Twitter a lot for Professional Development and find a ton of ideas out there--I just needed a way to organize them. I just starting playing with IFTTT.com --I love it--I use this to get pictures from Instagram in EN, my favorites from Twitter in EN, articles that I save from Instapaper in there also. I wanted a 1 click way to get ideas from Twitter in EN, and favoriting them in Twitter or saving to Instapaper are the easiest. All you need are the recipes from IFTTT
I have a class blog, and I also use IFTTT to get any additions from it into my student stack on Evernote---works amazingly well--instead of having to go to my blog, it is in the one place I go to most--EN!
Also, sometimes I get emails that I know I need to keep (tax stuff, financials, etc)--I use my Evernote email so I get them in my default mailbox.
These are just some of the many ways I use it!