diff --git a/mod/data/field/number/field.class.php b/mod/data/field/number/field.class.php
index 4035f501c98..da797ccba12 100644
--- a/mod/data/field/number/field.class.php
+++ b/mod/data/field/number/field.class.php
@@ -94,6 +94,16 @@ class data_field_number extends data_field_base {
         return $DB->sql_cast_char2real($fieldname, true);
     }
 
+    /**
+     * Check if a field from an add form is empty
+     *
+     * @param mixed $value
+     * @param mixed $name
+     * @return bool
+     */
+    function notemptyfield($value, $name) {
+        return strval($value) !== '';
+    }
 }
 
 
diff --git a/mod/data/field/text/field.class.php b/mod/data/field/text/field.class.php
index 90aee4c8d1d..9489db71f3b 100644
--- a/mod/data/field/text/field.class.php
+++ b/mod/data/field/text/field.class.php
@@ -43,6 +43,16 @@ class data_field_text extends data_field_base {
         return array(" ({$tablealias}.fieldid = {$this->field->id} AND ".$DB->sql_like("{$tablealias}.content", ":$name", false).") ", array($name=>"%$value%"));
     }
 
+    /**
+     * Check if a field from an add form is empty
+     *
+     * @param mixed $value
+     * @param mixed $name
+     * @return bool
+     */
+    function notemptyfield($value, $name) {
+        return strval($value) !== '';
+    }
 }
 
 
diff --git a/mod/data/field/textarea/field.class.php b/mod/data/field/textarea/field.class.php
index 5101a924fbd..cc6f395ce15 100644
--- a/mod/data/field/textarea/field.class.php
+++ b/mod/data/field/textarea/field.class.php
@@ -270,7 +270,8 @@ class data_field_textarea extends data_field_base {
         $names = explode('_', $name);
         // Clean first.
         if (count($names) == 2) {
-            return !empty($value);
+            // Don't assume that this is coming from a text editor with tags.
+            return strval($value) !== '';
         }
         return false;
     }