How to install ROS on a Raspberry Pi?

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I am trying to install ROS on a RPi 3 to use it to train middle school students in single arm industrial robotics.

pi@raspberrypi:~ $ cat /etc/os-release PRETTY_NAME="Raspbian GNU/Linux 8 (jessie)" NAME="Raspbian GNU/Linux" VERSION_ID="8" VERSION="8 (jessie)"

In order to use apt-get install for ROS I used instructions in the ROS wiki to modify my apt sources list. My ros-latest.list file in /etc/apt/sources.list.d reads

deb http://packages.ros.org/ros/ubuntu $(lsb_release -sc) main contrib non-free

but I get the following error when I run sudo apt-get update

W: Failed to fetch http://packages.ros.org/ros/ubuntu/dists/$(lsb_release/-sc)/binary-armhf/Packages  404  Not Found [IP: 140.211.166.134 80]
W: Failed to fetch http://packages.ros.org/ros/ubuntu/dists/$(lsb_release/main/binary-armhf/Packages  404  Not Found [IP: 140.211.166.134 80]
W: Failed to fetch http://packages.ros.org/ros/ubuntu/dists/$(lsb_release/contrib/binary-armhf/Packages  404  Not Found [IP: 140.211.166.134 80]
W: Failed to fetch http://packages.ros.org/ros/ubuntu/dists/$(lsb_release/non-free/binary-armhf/Packages  404  Not Found [IP: 140.211.166.134 80]

I suspect that I am doing something wrong with the $(lsb_release -sc) part of the ros-latest.list file.

Any ideas? I also plan to install Gazebo the same way if I can get ROS installed.