Use a recording of a whistled song and play it over and over around your bird. I know that I leave the tv on for my parrot when I leave the house and I would leave the channel on animal planet. Before too long he was making animal noises from the shows. If your bird keeps listening to the whistled song, eventually he will pick at least some of it up.
I want to teach my cockatiel to whistle songs. But I can't whistle. Can I use a plastic whistle? Is there any other way to teach him to whistle songs?
They generally have no problem picking up things like that and especially whistled tunes. I can't whistle either but my bird sure can, lol. Friends, t.v. Ect. Whistling is usually in a range they can pick up very quickly and easy and more natural for them. I did find this site for you in the first link. You can save them to a player on your computer and play them for your little one. Also save some youtube videos of other birds and things may work. I'm sure he'll be whistling lots of tunes in no time.