diff --git a/_includes/package-nav.html b/_includes/package-nav.html
index 1d63b42..27936cd 100644
--- a/_includes/package-nav.html
+++ b/_includes/package-nav.html
@@ -1,11 +1,13 @@
-<li><a href="04-tidy.html">Tidy data</a></li>
+<li><a href="tidy.html">Tidy data</a></li>
 <!--
-<li><a href="01-introduction.html">Introduction to data science</a></li>
-<li><a href="02-visualize.html">Visualize data</a></li>
-<li><a href="03-transform.html">Transform data</a></li>
-<li><a href="05-import.html">Import data</a></li>
-<li><a href="06-dates.html">Dates and times</a></li>
-<li><a href="07-strings.html">Regular expresssions</a></li>
-<li><a href="08-model.html">Model data</a></li>
-<li><a href="09-reporting.html">Reporting and reproducible research</a></li>
+<li class="dropdown-header">R for Data Science</li>
+<li><a href="intro.html">Introduction to data science</a></li>
+<li><a href="visualize.html">Visualize data</a></li>
+<li><a href="transform.html">Transform data</a></li>
+<li><a href="tidy.html">Tidy data</a></li>
+<li><a href="import.html">Import data</a></li>
+<li><a href="dates.html">Dates and times</a></li>
+<li><a href="strings.html">Regular expresssions</a></li>
+<li><a href="models.html">Model data</a></li>
+<li><a href="reports.html">Reporting and reproducible research</a></li>
 -->
diff --git a/04-tidy.Rmd b/tidy.Rmd
similarity index 100%
rename from 04-tidy.Rmd
rename to tidy.Rmd