diff --git a/docs/tutorials/data-modeling/core_extension.ipynb b/docs/tutorials/data-modeling/core_extension.ipynb
index 996bc88b1..b72de19ba 100644
--- a/docs/tutorials/data-modeling/core_extension.ipynb
+++ b/docs/tutorials/data-modeling/core_extension.ipynb
@@ -541,8 +541,8 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 15,
-   "id": "aeb1a9c1-727f-40ee-bf8b-5c6b0af0f027",
+   "execution_count": null,
+   "id": "888713e2-a68e-4b83-ae8e-36a1563c6e61",
    "metadata": {
     "editable": true,
     "slideshow": {
@@ -554,50 +554,11 @@
    },
    "outputs": [],
    "source": [
-    "from cognite.neat._utils.cdf.loaders import SpaceLoader"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 17,
-   "id": "575e3911-defd-4653-91b3-03c8d62060fb",
-   "metadata": {
-    "editable": true,
-    "slideshow": {
-     "slide_type": ""
-    },
-    "tags": [
-     "hide"
-    ]
-   },
-   "outputs": [
-    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "Deleted 11 views\n",
-      "Deleted 1 data models\n",
-      "Deleted space ['sp_doctrino_space']\n"
-     ]
-    }
-   ],
-   "source": [
-    "SpaceLoader(client).clean(\"sp_doctrino_space\")"
+    "# This cell is hidden so it does not show in the docs.\n",
+    "from cognite.neat._utils.cdf.loaders import SpaceLoader\n",
+    "\n",
+    "SpaceLoader(client).clean(\"sp_doctrino_space\");"
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "8023e501-98dd-4b44-aa2b-5959c0a21ca4",
-   "metadata": {
-    "editable": true,
-    "slideshow": {
-     "slide_type": ""
-    },
-    "tags": []
-   },
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {
diff --git a/mkdocs.yml b/mkdocs.yml
index 7a8fe14a5..e85fb9e3b 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -29,6 +29,8 @@ nav:
       - Data Onboarding:
         - Asset Hierarchy Migration: tutorials/data-onboarding/asset_hierarchy_migration.ipynb
         - Asset Hierarchy Migration with Type: tutorials/data-onboarding/asset_hierarchy_migration_with_type.ipynb
+      - Data Modeling:
+        - Extending Data Model: tutorials/data-modeling/core_extension.ipynb
   - Terminology:
       - Rules:
           - Overview: terminology/rules.md