Shared reading is when you and your students read an enlarged text together. Unlike reading aloud, the children are actually saying the words along with you. Unlike guided reading, there is just one copy of the text, that everyone can look at together (that's why it needs to be enlarged). Unlike some versions of close reading, shared reading involves reading the same short, engaging text, each day for many days. Usually (though not always) we're reading the whole text in one short ten or fifteen minute sitting.
The focus during shared reading is in on joyful reading for understanding, attending to the print and practicing foundational skills. Shared reading is also especially well-suited for studying language: vocabulary, patterns, rhymes, and can incorporate phonemic awareness in a meaningful context: initial sounds, ending sounds, onsets and rimes, and more.
You can use a wide variety of texts for shared reading: big books, songs, poems, readers' theater scripts, easy-to-read websites, short stories, speeches, diagrams, maps. Choose anything that is short, engaging, and lends itself to the skills you were hoping to focus on. For example, if you'd like to emphasize one-one matching, then you probably want a big book or a poem with large print, and plenty of space between each word, like Zoo Looking, by Mem Fox, or I Went Walking, by Sue Williams.
During shared reading, you and your children read in unison, with "one voice." The book is read over and over again so that the children become so familiar with the how the story goes that they can chime in and "read" along with you. Even emergent readers, who are not yet reading conventionally can chime in. Usually we use short, predictable texts so that it's easy for the kids to learn how the words go, making it fun and enjoyable to read along with you, matching their voices to each word you point to.
Lately, I've been using a lot of the books from the Brand New Readers Series for shared reading. There are many different characters to choose from in this series, and the levels of text complexity are just right for most kindergarten and first grade classrooms. I also love to use classics from the Wright Group, like Mrs. Wishy Washy by Joy Cowley.
Shared reading involves lots of rereading, often multiple times a day, for five days (or more!), allowing you to focus on something different each time you read the book. Usually the first time through, I read it just like I would read aloud any other book--with one big difference. I do make sure to point clearly to each word, and I use my voice to make the pattern stand out.
The second time through I continue to point to the words, and I also might let my voice trail off so that kids can fill in the missing words. Kids look to the pictures, and they know how the pattern goes, so they are able to figure out the words I'm leaving out. Substituting and filling in words that make sense is an important first phase in learning to read!
Many teachers make small copies of familiar shared reading texts available to kids in the classroom library, or in special folders or binders in each child's book bin or baggie.
Some parents will ask you, "But aren't they just memorizing it? That's not really reading is it?" Well, yes and no. When your child knows exactly how the book goes, he or she is able to put together many reading skills at once: using the picture to remember out what's happening on that page, pointing to one word at a time, making sure to say words that match what's happening on the page, turning one page at a time, reading with expression… and much more. All of these skills can come together somewhat easily when your child knows the story, even when they might not be able to practice these skills at all on "cold read."
For more on shared reading with young kids, I recommend the book Read It Again!: Revisiting Shared Reading by Brenda Parkes.
You can also learn more by watching this video; it nicely summarizes some of Don Holdaway's important work on shared reading.
Shared reading is usually thought of as a method for teaching emergent and beginning readers, but the same principles can still apply with older, more experienced readers as well. I've often used poems by Robert Frost, Martin Luther King's I Have a Dream speech, and lyrics of popular songs as material for shared reading with older kids. The focus is no longer on phonics, necessarily, but instead on figurative language, symbolism, historical context, deeper "hidden" meanings, and author's craft. When a text is loved by kids, it becomes part of their shared experience, fostering a community of readers. Years later, kids will say, "I remember when we did that song!"