diff --git a/free-programming-books.md b/free-programming-books.md
index 10d0b1a6..eab92eca 100644
--- a/free-programming-books.md
+++ b/free-programming-books.md
@@ -403,6 +403,7 @@
 * [Computational Thinking](https://www.cs.cmu.edu/~15110-s13/Wing06-ct.pdf) - Jeannette Wing, Carnegie-Mellon University (PDF)
 * [Computer Science I - Draft](https://bitbucket.org/chrisbourke/computersciencei/src) - Dr. Chris Bourke (PDF) (:construction: *in process*)
 * [Computer Science II - Draft](http://cse.unl.edu/~cbourke/ComputerScienceTwo.pdf) - Dr. Chris Bourke (PDF) (:construction: *in process*)
+* [CS Principles: Big Ideas in Programming](https://www.openbookproject.net/books/StudentCSP/) - Mark Guzdial and Barbara Ericson (HTML)
 
 
 #### Computer Vision