Yes there is.
in iTunes, plug in your old 4s and do a backup of the phone. Just to be safe.
You can then close itunes and open my computer. Your 4s should be showing as a phone in my computer, open it and then open only folder there. You should find all your pics stored there. You can select them and copy to a new folder on your desktop.
Once this is done, plug your iPhone 5 in and open iTunes. Then before you sync, go to the pictures tab and select the folder you created on your desktop with the old pics in it. You can unselect to sync music, apps or anything else you dont want. Then sync the phone and it should copy the pics from that folder onto your new iPhone 5!
Hope this helps