diff --git a/requirements/edx-sandbox/base.txt b/requirements/edx-sandbox/base.txt
index 931e15f88b..fbee5e0d6e 100644
--- a/requirements/edx-sandbox/base.txt
+++ b/requirements/edx-sandbox/base.txt
@@ -9,3 +9,4 @@ networkx==1.7
 sympy==0.7.1
 pyparsing==2.0.1
 nltk==2.0.4
+matplotlib==1.3.1