Update instructions

README.md

@@ -1,3 +1,22 @@
 # Enumerable Challenges
 
-More instructions and scaffolding coming soon.
+This repository follows our hero during a typical work day at WidgetCo. Over the course of the day, our hero will face coworkers who will present challenges that need some code written to solve a problem they're facing.
+
+You'll write tests based on the challenge and then an implementation to make those tests pass.
+
+How you structure your tests and your code is up to you (and part of the exercise). You can use your own sample data and structure it anyway you like.
+
+You should make the best possible use of Ruby's Enumerable API and TDD strategies. Your implementations should go in the `./lib` directory and your tests should go in the `./test` directory.
+
+## Submission Instructions
+
+* One member of your pair/group should [fork][] this repository to his or her account.
+* As you create files and solve the challenges, you should make frequent commits.
+* At the end of the session, you should create a pull request.
+
+[fork]: https://github.com/turingschool-examples/enumerable-challenges
+
+## Learning Goals
+
+* Demonstrate an understanding of the methods Ruby's Enumerable has to offer.
+* Implement TDD by creating tests and sample data from scratch.