diff --git a/01-monolith/tf-01.py b/01-monolith/tf-01.py
old mode 100644
new mode 100755
index 2ebf15b..3c74362
--- a/01-monolith/tf-01.py
+++ b/01-monolith/tf-01.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, string
 # the global list of [word, frequency] pairs
 word_freqs = []
diff --git a/02-code-golf/tf-02.py b/02-code-golf/tf-02.py
old mode 100644
new mode 100755
index 2151d19..91eba36
--- a/02-code-golf/tf-02.py
+++ b/02-code-golf/tf-02.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import re, string, sys
 
 stops = set(open("../stop_words.txt").read().split(",") + list(string.ascii_lowercase))
diff --git a/03-cookbook/tf-03.py b/03-cookbook/tf-03.py
old mode 100644
new mode 100755
index fa17574..2551f31
--- a/03-cookbook/tf-03.py
+++ b/03-cookbook/tf-03.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, string
 
 # The shared mutable data
diff --git a/04-candy-factory/tf-04.py b/04-candy-factory/tf-04.py
old mode 100644
new mode 100755
index 8c0f7cb..77057b9
--- a/04-candy-factory/tf-04.py
+++ b/04-candy-factory/tf-04.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 #
diff --git a/04-candy-factory/tf-04.sh b/04-candy-factory/tf-04.sh
old mode 100644
new mode 100755
diff --git a/05-kick-your-teammate-forward/tf-05.py b/05-kick-your-teammate-forward/tf-05.py
old mode 100644
new mode 100755
index 9996495..bd06173
--- a/05-kick-your-teammate-forward/tf-05.py
+++ b/05-kick-your-teammate-forward/tf-05.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 #
diff --git a/06-the-one/tf-06.py b/06-the-one/tf-06.py
old mode 100644
new mode 100755
index c114141..61c9903
--- a/06-the-one/tf-06.py
+++ b/06-the-one/tf-06.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 #
diff --git a/07-things/tf-07.py b/07-things/tf-07.py
old mode 100644
new mode 100755
index 989c079..9c71e3e
--- a/07-things/tf-07.py
+++ b/07-things/tf-07.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 from abc import ABCMeta
 
diff --git a/08-letterbox/tf-08.py b/08-letterbox/tf-08.py
old mode 100644
new mode 100755
index d0a37aa..38906b2
--- a/08-letterbox/tf-08.py
+++ b/08-letterbox/tf-08.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 class DataStorageManager():
diff --git a/09-kinds-of-things/tf-09.py b/09-kinds-of-things/tf-09.py
old mode 100644
new mode 100755
index 0302fd4..5ada00f
--- a/09-kinds-of-things/tf-09.py
+++ b/09-kinds-of-things/tf-09.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import abc, sys, re, operator, string
 
 #
diff --git a/10-hollywood/tf-10.py b/10-hollywood/tf-10.py
old mode 100644
new mode 100755
index 6f65f08..56bfefb
--- a/10-hollywood/tf-10.py
+++ b/10-hollywood/tf-10.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 #
diff --git a/11-bulletin-board/tf-11.py b/11-bulletin-board/tf-11.py
old mode 100644
new mode 100755
index 71be4b8..f04338c
--- a/11-bulletin-board/tf-11.py
+++ b/11-bulletin-board/tf-11.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 #
diff --git a/12-inverse-multiplexer/tf-12.py b/12-inverse-multiplexer/tf-12.py
old mode 100644
new mode 100755
index 2cb097a..211932f
--- a/12-inverse-multiplexer/tf-12.py
+++ b/12-inverse-multiplexer/tf-12.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 #
diff --git a/13-double-inverse-multiplexer/tf-13.py b/13-double-inverse-multiplexer/tf-13.py
old mode 100644
new mode 100755
index 56fff56..039fe2e
--- a/13-double-inverse-multiplexer/tf-13.py
+++ b/13-double-inverse-multiplexer/tf-13.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string
 
 #
diff --git a/14-tabular/tf-14.py b/14-tabular/tf-14.py
old mode 100644
new mode 100755
index 4633eac..26fb439
--- a/14-tabular/tf-14.py
+++ b/14-tabular/tf-14.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, string, sqlite3
 
 #
diff --git a/15-restful/tf-15.py b/15-restful/tf-15.py
old mode 100644
new mode 100755
index 0adc9a4..19e9b49
--- a/15-restful/tf-15.py
+++ b/15-restful/tf-15.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import re, string, sys
 
 with open("../stop_words.txt") as f:
diff --git a/16-asides/tf-16.py b/16-asides/tf-16.py
old mode 100644
new mode 100755
index a92fca9..c8cba69
--- a/16-asides/tf-16.py
+++ b/16-asides/tf-16.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 import sys, re, operator, string, time
 
 #
diff --git a/test/test.sh b/test/test.sh
index 318b648..ff7d1c9 100755
--- a/test/test.sh
+++ b/test/test.sh
@@ -11,17 +11,20 @@ files=$(echo *.txt)
 for dir in ../[0-9][0-9]-* ; do
     cd $dir
     for file in $files ; do
-        exe=$(echo tf-[0-9][0-9].py)
-        msg testing $(basename $dir)/$exe with $file
-        python $exe ../$file | diff -b - $mydir/$file
-        result=$?
-        total=$((total+1))
-        if [ $result -ne 0 ]; then
-            failures=$(($failures+1))
-            msg FAILED!
-        else
-            msg passed.
-        fi
+        for exe in * ; do
+            if [ -x $exe ]; then
+                msg testing $(basename $dir)/$exe with $file
+                ./$exe ../$file | diff -b - $mydir/$file
+                result=$?
+                total=$((total+1))
+                if [ $result -ne 0 ]; then
+                    failures=$(($failures+1))
+                    msg FAILED!
+                else
+                    msg passed.
+                fi
+            fi
+        done
     done
     cd $mydir
 done