Here's a little trick, which I never use, but know about for getting .edu domains (I don't like spamming, instead I like helping people and getting organic traffic)
Type in Google:
site:.edu inurl:blog "post a comment" -"comments closed" -"you must be logged in" "add keyword"
Example:
site:.edu inurl:blog "post a comment" -"comments closed" -"you must be logged in" "green energy"
There are many ways you can edit this.