diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..8b0a108
Binary files /dev/null and b/.DS_Store differ
diff --git a/javascript/100_aggregation_pipeline_match.ipynb b/javascript/100_aggregation_pipeline_match.ipynb
index b1ece11..d3f4dd9 100644
--- a/javascript/100_aggregation_pipeline_match.ipynb
+++ b/javascript/100_aggregation_pipeline_match.ipynb
@@ -86,36 +86,6 @@
     "});"
    ]
   },
-  {
-   "cell_type": "markdown",
-   "id": "9f6caab3",
-   "metadata": {},
-   "source": [
-    "### Exercise: get all books from 2010 and 2012"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "polar-pride",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "const booksFrom2010and2012 = [\n",
-    "    { $match: { \n",
-    "        year: 2010,\n",
-    "        // add code here!\n",
-    "    } \n",
-    "    }\n",
-    " ];\n",
-    " \n",
-    " const cursor = await books.aggregate( booksFrom2010and2012 );\n",
-    " \n",
-    " await cursor.forEach((b) => {\n",
-    "    console.log(b);\n",
-    " });"
-   ]
-  },
   {
    "cell_type": "markdown",
    "id": "a6717c30",
diff --git a/javascript/101_aggregation_pipeline_arrays.ipynb b/javascript/101_aggregation_pipeline_arrays.ipynb
index d26a0e9..f89516e 100644
--- a/javascript/101_aggregation_pipeline_arrays.ipynb
+++ b/javascript/101_aggregation_pipeline_arrays.ipynb
@@ -87,7 +87,7 @@
     "  {\n",
     "    $project: {\n",
     "      title: 1,\n",
-    "      genre: 1,\n",
+    "      genres: 1,\n",
     "    },\n",
     "  },\n",
     "];\n",
@@ -126,7 +126,7 @@
     "  {\n",
     "    $project: {\n",
     "      title: 1,\n",
-    "      genre: 1,\n",
+    "      genres: 1,\n",
     "    },\n",
     "  },\n",
     "];\n",
diff --git a/javascript/103_aggregation_pipeline_lookup.ipynb b/javascript/103_aggregation_pipeline_lookup.ipynb
index e3f976a..02be24d 100644
--- a/javascript/103_aggregation_pipeline_lookup.ipynb
+++ b/javascript/103_aggregation_pipeline_lookup.ipynb
@@ -89,7 +89,7 @@
     "  {\n",
     "    $project: {\n",
     "      _id: 0,\n",
-    "      title: 1,\n",
+    "      name: 1,\n",
     "      books: 1,\n",
     "      booksWritten: 1,\n",
     "    },\n",