diff --git a/demo/erratic-turtle-graphics-launcher.js b/demo/erratic-turtle-graphics-launcher.js
index f9aac6e..060cd89 100644
--- a/demo/erratic-turtle-graphics-launcher.js
+++ b/demo/erratic-turtle-graphics-launcher.js
@@ -51,7 +51,7 @@
         options: options,
         onchange: function(option) {
           program = option.value;
-          programTextarea.innerHTML = program;
+          programTextarea.value = program;
           run();
         }
       })