diff --git a/inc/school.inc b/inc/school.inc
--- a/inc/school.inc
+++ b/inc/school.inc
@@ -296,7 +296,7 @@ function school_instructions_html($schoo
  */
 function school_semesters(array $school)
 {
-  if (!$school['crawled'])
+  if (empty($school['crawled']))
     return array();
   return $school['semesters'];
 }