A great way to learn Science!
You know you have a good rhyme, when a kid sing alongside with you and dance enjoying the rhyme

Though some people find it hard to construct lyrics that rhyme, rhyming is important and is worth persevering with. As highly successful songwriter Janis Ian says in The Songwriters Workshop, “A rhyme scheme helps to hypnotise, to force its way into our listening selves.” Others have observed that a good rhyme scheme gives the listener a pleasant feeling of resolution and security. Not every song has to rhyme, but so many of the good ones do that there must be something in it! Don’t overdo it, though — a bad or over-extended rhyme scheme can be irritating to the listener and can distract attention from what you’re trying to say. If you have to make a line sound stupid in order for it to rhyme, throw it away and start again.