diff --git a/public/mod/assign/templates/grading_actions.mustache b/public/mod/assign/templates/grading_actions.mustache
index aa2ccb1e19a..ad33703dc4e 100644
--- a/public/mod/assign/templates/grading_actions.mustache
+++ b/public/mod/assign/templates/grading_actions.mustache
@@ -33,7 +33,7 @@
 <div class="d-flex justify-content-between">
     <form data-region="grading-actions-form" class="hide flex-grow-1 align-self-center">
         <label>{{#str}}sendstudentnotifications, mod_assign{{/str}}
-               <input type="checkbox" name="sendstudentnotifications"
+               <input type="checkbox" name="sendstudentnotifications" class="form-check-input"
                       {{#defaultsendnotifications}}checked="checked"{{/defaultsendnotifications}} />
         </label>
         {{#helpicon}}