State a particular digraph sound to students; /sh/, for example. Explain to children that the sound is made by two letters, S and H, and write the two letters on the board. Ask them to say the sound as you point to the letters.
Inform students that you are going to say a variety of words, some that begin with the given digraph and some that don't; in this case, /sh/. Tell students that upon hearing a word that begins with the /sh/ sound, they are to raise their hands.
List several different words; some that begin with /sh/ and some that don't. As you say the words, look for students to raise their hands when they hear a word that begins with the /sh/ sound. Provide clarification if you notice students aren't understanding the task.
Make the activity more challenging. Once students exhibit that they are able to identify the sound at the beginning of words, have them identify the sound in the middle and end of words. Inform students of the new task. As you say words that have the /sh/ digraph in the middle or at the end, students should raise their hands to indicate that they hear the sound in the words.
Write a list of words on chart paper that contains a specific digraph, as well as words that don't contain the digraph. Hang the chart paper in the front of the class.
Write a digraph on the board. Explain to students the sound that the given digraph makes. Explain that the given combination of letters are found in a variety of words.
Direct students' attention to the chart paper. Inform them that there are words on the chart paper that contain the given digraph.
Invite one student to come to the chart paper. Instruct her to look through the list of words and circle a word with a marker that contains the digraph. Upon circling a word that contains the digraph, read it out loud and have students repeat the word.
Follow the same procedure, inviting each student to circle a word that contains the digraph on the list. Continue the activity until all of the words that contain the digraph have been circled.