First, I teach the students the following poem. After they are comfortable, I like to add a simple steady beat (pat, clap). After the students can perform the poem well, I ask them to listen as I change something. I read the poem again, this time adding a long pause on the word, "huge." The students then perform with me.
I introduce the fermata symbol and definition and have the students practice drawing the symbol in the air. We perform the poem again, this time drawing the fermata in the air on the word, "huge." We then move the fermata to different words in the poem and perform the fermatas.
Next, I have the students get into small groups and experiment with the fermata on a variety of words. Once they have their poem like they want it, they practice it together. This gives them a chance to practice drawing the fermata as well as discover where fermatas might naturally fit in a piece.
Each group then performs for the class and the other students have to locate the words that had a fermata. The students pick volunteers to come to the board and put the symbols in the correct place.
There is also a great Orff lesson using the song, "It Rained on Anne," in Konnie Saliba's book, "A Musical Adventure." You can check it out here.