diff --git a/collects/test-engine/scheme-tests.ss b/collects/test-engine/scheme-tests.ss
index 67e0090568..89e72076dd 100644
--- a/collects/test-engine/scheme-tests.ss
+++ b/collects/test-engine/scheme-tests.ss
@@ -17,10 +17,14 @@
 
 (define INEXACT-NUMBERS-FMT
   "check-expect cannot compare inexact numbers. Try (check-within test ~a range).")
+(define FUNCTION-FMT
+  "check-expect cannot compare functions.")
 (define CHECK-ERROR-STR-FMT
   "check-error requires a string for the second argument, representing the expected error message. Given ~s")
 (define CHECK-WITHIN-INEXACT-FMT
   "check-within requires an inexact number for the range. ~a is not inexact.")
+(define CHECK-WITHIN-FUNCTION-FMT
+  "check-within cannot compare functions.")
 
 (define-for-syntax CHECK-EXPECT-STR
   "check-expect requires two expressions. Try (check-expect test expected).")
@@ -113,7 +117,8 @@
 ;; check-values-expected: (-> scheme-val) scheme-val src -> void
 (define (check-values-expected test actual src test-info)
   (error-check (lambda (v) (if (number? v) (exact? v) #t))
-               actual INEXACT-NUMBERS-FMT)
+               actual INEXACT-NUMBERS-FMT #t)
+  (error-check (lambda (v) (not (procedure? v))) actual FUNCTION-FMT #f)
   (send (send test-info get-info) add-check)
   (run-and-check (lambda (v1 v2 _) (beginner-equal? v1 v2))
                  (lambda (src v1 v2 _) (make-unequal src v1 v2))
@@ -130,7 +135,8 @@
     [_ (raise-syntax-error 'check-within CHECK-WITHIN-STR stx)]))
 
 (define (check-values-within test actual within src test-info)
-  (error-check number? within CHECK-WITHIN-INEXACT-FMT)
+  (error-check number? within CHECK-WITHIN-INEXACT-FMT #t)
+  (error-check (lambda (v) (not (procedure? v))) actual CHECK-WITHIN-FUNCTION-FMT #f)
   (send (send test-info get-info) add-check)
   (run-and-check beginner-equal~? make-outofrange test actual within src
                  test-info
@@ -147,7 +153,7 @@
     [_ (raise-syntax-error 'check-error CHECK-ERROR-STR stx)]))
 
 (define (check-values-error test error src test-info)
-  (error-check string? error CHECK-ERROR-STR-FMT)
+  (error-check string? error CHECK-ERROR-STR-FMT #t)
   (send (send test-info get-info) add-check)
   (let ([result (with-handlers ([exn?
                                  (lambda (e)
@@ -165,9 +171,9 @@
         #t)))
 
 
-(define (error-check pred? actual fmt)
+(define (error-check pred? actual fmt fmt-act?)
   (unless (pred? actual)
-    (raise (make-exn:fail:contract (format fmt actual)
+    (raise (make-exn:fail:contract (if fmt-act? (format fmt actual) fmt)
                                    (current-continuation-marks)))))