diff --git a/src/exercise/06.md b/src/exercise/06.md
index da592feb1..11c8092c7 100644
--- a/src/exercise/06.md
+++ b/src/exercise/06.md
@@ -33,6 +33,8 @@ Production deploys:
 - [Exercise](https://advanced-react-hooks.netlify.com/isolated/exercise/06.js)
 - [Final](https://advanced-react-hooks.netlify.com/isolated/final/06.js)
 
+> Note: useDebugValue values will not show in production, because the production build of useDebugValue does nothing.
+
 In this exercise, we have a custom `useMedia` hook which uses
 `window.matchMedia` to determine whether the user-agent satisfies a given media
 query. In our `Box` component, we're using it three times to determine whether