diff --git a/clean_docker.sh b/clean_docker.sh
index 47a3e7b..adc7479 100755
--- a/clean_docker.sh
+++ b/clean_docker.sh
@@ -1,3 +1,4 @@
+#!/bin/bash
 EXITED=$(docker ps -q -f status=exited)
 DANGLING=$(docker images -q -f "dangling=true")
 DANGLING_VOLUME=$(docker volume ls -qf "dangling=true")
diff --git a/s/cut_smaller_video.sh b/s/cut_smaller_video.sh
index 76b89aa..137ae68 100755
--- a/s/cut_smaller_video.sh
+++ b/s/cut_smaller_video.sh
@@ -1,2 +1,3 @@
+#!/bin/bash
 ./s/ffmpeg -y -i /files/v/bunny_1080p_60fps.mp4 -ss 00:01:24 -t 00:00:10  /files/v/small_bunny_1080p_60fps.mp4
 ./s/ffmpeg -y -i /files/v/bunny_1080p_30fps.mp4 -ss 00:01:24 -t 00:00:10  /files/v/small_bunny_1080p_30fps.mp4
diff --git a/s/download_video.sh b/s/download_video.sh
index 603dda6..8ba71a9 100755
--- a/s/download_video.sh
+++ b/s/download_video.sh
@@ -1,2 +1,3 @@
+#!/bin/bash
 wget -O v/bunny_1080p_60fps.mp4 http://distribution.bbb3d.renderfarming.net/video/mp4/bbb_sunflower_1080p_60fps_normal.mp4
 wget -O v/bunny_1080p_30fps.mp4 http://distribution.bbb3d.renderfarming.net/video/mp4/bbb_sunflower_1080p_30fps_normal.mp4
diff --git a/s/start_jupyter.sh b/s/start_jupyter.sh
index 62925cc..6c89a6c 100755
--- a/s/start_jupyter.sh
+++ b/s/start_jupyter.sh
@@ -1 +1,2 @@
+#!/bin/bash
 docker run --rm -p 8888:8888 -v $(pwd):/home/jovyan/work jupyter/scipy-notebook
diff --git a/setup.sh b/setup.sh
index acc7af1..77156d6 100755
--- a/setup.sh
+++ b/setup.sh
@@ -1,3 +1,4 @@
+#!/bin/bash
 check_cmd()
 {
   if ! which $1 &>/dev/null; then