diff --git a/lib/kgrader/cli.rb b/lib/kgrader/cli.rb
index d14e772..54351a4 100644
--- a/lib/kgrader/cli.rb
+++ b/lib/kgrader/cli.rb
@@ -38,7 +38,7 @@ module KGrader
 
     def clean
       clear_jail
-      # TODO: also purge uncommitted grades: set all graded to ungraded and delete all pending files
+      clean_desk
     end
 
     def clobber
@@ -73,5 +73,12 @@ module KGrader
     def clear_desk
       FileUtils.rm_rf Dir[File.join @fs.desk, '*', '']
     end
+
+    def clean_desk
+      Dir[File.join @fs.desk, '*', '*', '*', '*', 'status.txt'].each do |fn|
+        File.write fn, "ungraded" if File.read(fn) == "graded"
+      end
+      FileUtils.rm_rf Dir[File.join @fs.desk, '*', '*', '*', '*', 'pending']
+    end
   end
 end
diff --git a/lib/kgrader/submission.rb b/lib/kgrader/submission.rb
index 48a876c..ecbfa51 100644
--- a/lib/kgrader/submission.rb
+++ b/lib/kgrader/submission.rb
@@ -73,19 +73,19 @@ module KGrader
 
     private
     def repo
-      File.join @root, "repo"
+      File.join @root, 'repo'
     end
 
     def statusfile
-      File.join @root, "status.txt"
+      File.join @root, 'status.txt'
     end
 
     def gradefile
-      File.join @root, "grade.txt"
+      File.join @root, 'grade.txt'
     end
 
     def pendingfile
-      File.join @root, "pending"
+      File.join @root, 'pending'
     end
 
     def revision