Give the students an oral example by summarizing a story they know -- Sleeping Beauty, Peter Rabbit, Hansel and Gretel -- without telling them the title. Ask them what story they just heard and when they tell you, explain that instead of reading ten pages from a book, you summarized it for them.
Divide the students into pairs and have them tell each other stories and see if the other student know which one it is. Circulate around the room and listen to the way students are telling the stories to make sure they aren't getting bogged down in detail.
Model summarizing. Start your lessons with, "Today we are going to learn about Mars, but before we being I want to summarize what we learned about Pluto yesterday." Involve the students by asking them to be able to summarize yesterday's lessons.
Teach the kids about topic sentences and how to spot them. Put a report -- you only need a paragraph - on white board and give the students a copy. Have them read the sample and pick out the most important sentence. Practice this exercise with various topics until they become proficient at it.
Move on to supporting detail. Have the students identify which ideas support the thesis statement and which sentences can be deleted because they are repeated or irrelevant to the essence of the article.
Assign summarizing exercises. This can be done both as in-class assignments and for homework. Adopt the "practice makes perfect" approach.
Incorporate summarizing exercises into all subjects. Rather than looking at summarizing as an activity for an English or social studies class, use it in science, math and physical education. Give the students an oral assignment and have them summarize it for you.
Test the kids to find out how well they learned to summarize. Giving them a formal assignment that you mark assesses how well you taught the kids to summarize.