diff --git a/TODO.md b/TODO.md
index 152c27e..99e9c47 100644
--- a/TODO.md
+++ b/TODO.md
@@ -8,3 +8,4 @@
 * [ ] Support for multiple hidden layers
 * [ ] Support for different activation functions
 * [ ] Combine with ml5 / deeplearnjs.
+* [ ] Coding Challenge: the "Hello World" of NN - handwritten number recognition