My itunes library on my laptop shows songs that are not showing on my ipod. what could be wrong?

Assuming that the songs play in your iTunes Library, either an incomplete Sync or the items have not been included in the Sync settings.

Try another Sync, do any of the songs then make it onto the iPod? If so, that indicates an incomplete Sync and there's not much you can do except try again. It's been a long-time bug that is not likely to be fixed now.

Regarding whether the items have been included in the list to Sync, howe do you synchronise your library? Is it Sync entire library or is it Sync selected playlists, artists, albums and genres?