diff --git a/collects/handin-server/overridden-collects/fake-teachpack/htdp/guess.ss b/collects/handin-server/overridden-collects/fake-teachpack/htdp/guess.ss
new file mode 100644
index 0000000000..757c4a8144
--- /dev/null
+++ b/collects/handin-server/overridden-collects/fake-teachpack/htdp/guess.ss
@@ -0,0 +1,31 @@
+#lang scheme/gui
+
+(require htdp/error lang/prim)
+
+(provide guess-with-gui guess-with-gui-3 guess-with-gui-list)
+
+(define-higher-order-primitive guess-with-gui guess-with-gui/proc
+  (check-guess))
+(define-higher-order-primitive guess-with-gui-3 guess-with-gui-3/proc
+  (check-guess))
+(define-higher-order-primitive guess-with-gui-list guess-with-gui-list/proc
+  (_ check-guess-list))
+
+(define (convert guesses:vec)
+  (void))
+
+(define (guess-with-gui/proc cg)
+  (check-proc 'guess-with-gui cg 2 'first "two arguments")
+  (void))
+
+(define (guess-with-gui-3/proc cg)
+  (check-proc 'guess-with-gui-3 cg (+ 3 1) 'first "four arguments")
+  (void))
+
+(define (guess-with-gui-list/proc n cg)
+  (check-arg  'guess-with-gui-list
+              (and (number? n) (integer? n) (>= n 1)) "positive integer" '1st n)
+  (check-proc 'guess-with-gui-list cg 2 'first "two arguments")
+  (unless  (<= (expt 10 n) 2147483647)
+    (error 'guess-with-gui-list "the given number of digits (~a) is too large" n))
+  (void))
diff --git a/collects/handin-server/overridden-collects/readme.txt b/collects/handin-server/overridden-collects/readme.txt
index a73c86303f..5f502b1aab 100644
--- a/collects/handin-server/overridden-collects/readme.txt
+++ b/collects/handin-server/overridden-collects/readme.txt
@@ -4,3 +4,11 @@ that appear here will be used instead of ones in the PLT tree or the
 user-local collections.  Use it to override collections that are safe
 for testing, for example -- avoid using actual gui.  See also the
 documentation for `sandbox-override-collection-paths' in "doc.txt".
+
+This is currently used with the `teachpack' collection.  Note that
+mzscheme resolved collection directories based on toplevel names only,
+which means that if we actually use `teachpack' for the directory
+name, then files that are not here will not be searched in the usual
+plt tree.  Because of this the collection is called `fake-teachpack',
+and checkers should specify requires in this collection if submissions
+need a fake teachpack.