I'm a grad student. We're looking for a remote site to perform shellshock for educational purposes. Sites which are willingly vulnerable for ethical hacking purposes??
There were a few sites but they are no longer online. Your best bet is to grab a VM and perform the test locally. There's a good VM and Walkthrough available from PentesterLab - https://pentesterlab.com/exercises/cve-2014-6271
Take a look at: http://www.cis.syr.edu/~wedu/Teaching/CompSec/labs.html
There are a whole set of free labs (including shellshock), an unpatched Ubuntu image, and even instructions on how to set up VirtualBox to run the VM on your own machine if you are unfamiliar.
An excellent resource that we use for our classes. Have fun!