diff --git a/docs/01-Collecting-and-displaying-data-in-GSheets.md b/docs/01-Collecting-and-displaying-data-in-GSheets.md
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@@ -1,7 +0,0 @@
----
-layout: page
-title: Lecture 1
-nav_order: 2
-description: Lecture 1: Collecting and displaying data in Google Sheets
----
-# Lecture 1: Collecting and displaying data in Google Sheets
diff --git a/docs/01-What-is-data.md b/docs/01-What-is-data.md
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--- /dev/null
+++ b/docs/01-What-is-data.md
@@ -0,0 +1,7 @@
+---
+layout: page
+title: Lecture 1
+nav_order: 2
+description: Lecture 1: What is data
+---
+# Lecture 1: What is data
diff --git a/docs/02-Collecting-and-displaying-data-in-GSheets.md b/docs/02-Collecting-and-displaying-data-in-GSheets.md
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+++ b/docs/02-Collecting-and-displaying-data-in-GSheets.md
@@ -0,0 +1,7 @@
+---
+layout: page
+title: Lecture 2
+nav_order: 3
+description: Lecture 2: Collecting and displaying data in Google Sheets
+---
+# Lecture 2: Collecting and displaying data in Google Sheets
diff --git a/docs/404.html b/docs/404.html
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----
-permalink: /404.html
-layout: default
----
-
-<style type="text/css" media="screen">
-  .container {
-    margin: 10px auto;
-    max-width: 600px;
-    text-align: center;
-  }
-  h1 {
-    margin: 30px 0;
-    font-size: 4em;
-    line-height: 1;
-    letter-spacing: -1px;
-  }
-</style>
-
-<div class="container">
-  <h1>404</h1>
-
-  <p><strong>Page not found :(</strong></p>
-  <p>The requested page could not be found.</p>
-</div>