Removing photos and songs from iPad storage after sync turned off

After turning off iCloud sync for Music and Photos, how do I remove the songs and photos that are already there? I'm setting up an iPad which has a very small amount of storage. I had hoped that iCloud services would intelligently use the space so I could prioritize apps, and only use storage for photos and songs when it was available. However it quickly loaded 7.4 gigs of songs and 4 gigs of images. When I wanted to install more apps, it refused. So I turned off sync for my music library and my photo library. I thought this would remove the songs and photos. I've restarted the iPad and searched the interfaces. Is there any way to remove these songs and images? Note, if I need to reset the iPad and restore from a backup, that's ok. I'm wondering if the backup I make now will preserve the settings I have now, which would imply that no photos or songs should be loaded.