Songs fail to sync

Hello, I always sync with my mac with iTunes and i wanted my new music on both my iPhone and iPad but both wouldn't download the songs from my mac but it worked for my iPod nano so what I did with my iPhone I restored it and it worked fine and I didn't restore at all I just downloaded my apps again so for my iPad I don't want yo restore because it has a certificate for my schools wifi so I need it any ideas on how to fix this?