Plant that tastes like licorice- what is it?!?

I live in Portland, Oregon, and outside of my school there's a dark green grassy looking plant that grows off of a tall stem. The tallest I've seen is about a foot and a half tall... All of the kids chew on it, I've tried it myself and it truly does taste like black licorice. I looked on Google Images at licorice plants and a friend suggested anise- but none resemble the plant I'm thinking of. Any help?