Introduce preschoolers to the concept of rhyming by using their own names. When children are gathered together, give each child the chance to come up with a word that rhymes with his own name. They can be nonsense words. For instance, a child named Charles might rename himself "Charles Schmarles" or "Charles Barles." Once each child has chosen his name, invite the entire group to sing a simple song using it. For instance, "Good morning to you, good morning to you, good morning Charles Schmarles, good morning to you!"
A rhyming guessing game requires no materials so it can be played anywhere at any time. Speak a sentence for preschoolers, substituting one real word with a real or made-up word that rhymes with it. For instance, say "Sheila's favorite thing to eat is corn on the slob." Children can tell you which word is wrong and what the real word should be. Once children understand the game, invite them to create their own sentences and challenge one another.
Hanging rhyming words on the wall allows children to review them every day. Hang a pocket chart on the wall. Each time you read a book to the class, ask children to listen for rhyming words. When they hear two words that rhyme, write these words onto index cards and hang them on the chart together. When you find multiple pairs of words that rhyme with one another, group them all together on the chart.
Help children practice sorting and rhyming at the same time. Choose four or five simple items whose names have many common rhymes. Print a picture of each item, label it, and tape it to the front of a shoe box. Write as many words as you can think of that rhyme with these main words on index cards. Pull out one card at a time and ask children to sort it into the correct box. Although children won't necessarily be able to read the words you're pulling out, encourage them to look at the end of the word to match it to a shoe box word.