diff --git a/schema/pretext-dev.rnc b/schema/pretext-dev.rnc
index 07f72665ae..af3d2af973 100644
--- a/schema/pretext-dev.rnc
+++ b/schema/pretext-dev.rnc
@@ -469,14 +469,20 @@
                 attribute number {text}?,
                 StatementExercise,
                 Feedback?,
+                Matches,
+                Hint*, Answer*, Solution*
+            Matches = (
                 element matches {
                     Match+
-                },
-                Hint*, Answer*, Solution*
+                } |
+                element cardsort {
+                    Match+
+                })
             Match =
                 element match {
                     attribute order {xsd:integer}?,
                     element premise {
+                        attribute order {xsd:integer}?,
                         mixed {BlockText?}
                     },
                     element response {
diff --git a/schema/pretext-dev.rng b/schema/pretext-dev.rng
index 542bece53a..7e2c03bd4e 100644
--- a/schema/pretext-dev.rng
+++ b/schema/pretext-dev.rng
@@ -1281,11 +1281,7 @@
     <optional>
       <ref name="Feedback"/>
     </optional>
-    <element name="matches">
-      <oneOrMore>
-        <ref name="Match"/>
-      </oneOrMore>
-    </element>
+    <ref name="Matches"/>
     <zeroOrMore>
       <ref name="Hint"/>
     </zeroOrMore>
@@ -1296,6 +1292,20 @@
       <ref name="Solution"/>
     </zeroOrMore>
   </define>
+  <define name="Matches">
+    <choice>
+      <element name="matches">
+        <oneOrMore>
+          <ref name="Match"/>
+        </oneOrMore>
+      </element>
+      <element name="cardsort">
+        <oneOrMore>
+          <ref name="Match"/>
+        </oneOrMore>
+      </element>
+    </choice>
+  </define>
   <define name="Match">
     <element name="match">
       <optional>
@@ -1304,6 +1314,11 @@
         </attribute>
       </optional>
       <element name="premise">
+        <optional>
+          <attribute name="order">
+            <data type="integer"/>
+          </attribute>
+        </optional>
         <mixed>
           <optional>
             <ref name="BlockText"/>
diff --git a/schema/pretext.xml b/schema/pretext.xml
index 36622fd0c3..9107680fef 100644
--- a/schema/pretext.xml
+++ b/schema/pretext.xml
@@ -2424,14 +2424,20 @@
                 attribute number {text}?,
                 StatementExercise,
                 Feedback?,
+                Matches,
+                Hint*, Answer*, Solution*
+            Matches = (
                 element matches {
                     Match+
-                },
-                Hint*, Answer*, Solution*
+                } |
+                element cardsort {
+                    Match+
+                })
             Match =
                 element match {
                     attribute order {xsd:integer}?,
                     element premise {
+                        attribute order {xsd:integer}?,
                         mixed {BlockText?}
                     },
                     element response {