It depends on what you want to do with those photos. If you want them to sync through iTunes on your son's Mac, then copying them to that Mac (by whatever means) is the only practical way. Trying to move the iPad back and forth between to computer is possible, but best reserved for those time you don't' have a choice. There are too many things to go wrong if you don't do it just right, and it's not a quick procedure.
If you just want them on your camera roll you can try several different apps. Most will require that you be able to join your work computer's network with the iPad. If you can do that, my favorite is PhotoSync (one word). PhotoSync has a mode where it becomes a webpage of sorts. You type the suppled URL into the computer browser and copy photos that way.
GoodReader can do the same thing, only the photos will be stored in GoodReader's file space. However, great as GoodReader is at many things, it's not much of a photo organizer/viewer.
You could use either of these two apps with the iPad to transport the pictures between the two computers.
Or you could use a cloud service like DropBox or Box.com to do the same thing via the internet; no iPad required.
There are other third party apps that will store and organize your photos separate from the Photo app. Most of them have photo transfer options similar to the ones mentioned. The more popular are Photo Manager Pro and Photo-Sort.