Too much music, too little ipod

It's easier to use playlists and select to sync only selected playlists to your husband's iPod (in the Music tab). You can use playlists you already have, or make a new playlist just for him. You can drag whole albums or individual songs to his playlists. You can easily change his playlists by adding or deleting songs at will without affecting your library. This avoids problems with unchecked songs not playing in iTunes or on your iPod Classic.