Separate out potentially offensive cow files in cowsay

I work with a group that teaches kids how to program. For learning the Linux command line, we wanted to throw in some fun commands in addition to the standard ones. Introducing cowsay would be great except that some of the included cow files (e.g., sodomized-sheep, etc.) will certainly offend some parents. If nothing else, they'll distract from the lesson.

The kids primarily use Ubuntu and would use apt-get to install cowsay. I am unfamiliar with how the package management process works, but would it be possible to split the cowsay package into cowsay and cowsay-extras where the cow and maybe a few non-offensive others are in the base package? Or could there be a cowsay-off package in a similar way that there's a fortunes-off package? The offensive cow files don't need to be removed from Ubuntu altogether. It would just be nice to avoid surprises from the benign-sounding cowsay package.