Teach him to sing songs instead? Michael said if he likes rhyming words then have him pick out the words that rhyme in the song. Or to pick out real things in the house that rhyme (chair and bear) together. Or, if you want a laugh, try to get him to find something that rhyme's with orange (j/k).
So, last night after dinner JI crawled into my lap. I said to him, "Let's play a game. What rhymes with red?"
He looked at me like I was from Mars then said a bunch of silly nonsensical words (none of which rhymed with red).
To give him a hint, I pointed to his head.
He said, "Knowledge?!"
No, what rhymes with red?