Strategy #3: Identifying supporting details first

When students struggle to locate the main idea of a paragraph, they can use this process of elimination strategy. By identifying the supporting details first, they can narrow down the paragraph's contents to arrive at the main idea. Here are instructions you can give to your students:

Locate the 3 E's--examples, evidence, and explanations--to identify the supporting details of the following passage. Then if there is a sentence left, consider whether it is the main idea. It helps to have various colored highlighters, one for each type of supporting material, and to create a color code as this student did here:


Signal detection can also have life-or-death consequences when people are responsible for watching an airport scanner for weapons, monitoring patients from an intensive-car nursing station, or detecting radar blips. Studies have shown, for example, that people's ability to catch a faint signal diminishes after about 30 minutes. But this diminishing response depends on the task, on the time of day, and even on whether the participants periodically exercise (Warm & Dember, 1986). Experience matters, too. In one experiment, 10 hours of action video game playing--scanning for and instantly responding to any intrusion--increased novice players' signal detection skills (p. 199-200)

Passage from: Myers, D. G. (2007). Psychology. (8th ed.). New York: Worth Publishers.

By first identifying the examples, evidence, and explanations, we then see that this paragraph's main idea comes at the start: "Signal detection can also have life-or-death consequences." If, however, all the sentences in a paragraph are identified as examples, evidence and explanation, perhaps there is an implied main idea--one that is not stated directly. Students should then consider the context of the previous and subsequent paragraphs to determine the implied main idea. Finally, remind students to look for key words that signal examples, evidence, and other supporting ideas. Strengthening their awareness of signal words such as "for example, as, like, imagine" can improve their reading comprehension.

Again, please do not recommend that students do this every time they read. This is a good exercise to do together to help them understand the patterns presented in textbooks. Faculty should also recommend students stop and try this strategy when the reading is especially challenging. However, consistently reading with this strategy will be very time consuming, and some students will be distracted by the task of changing colors.