At first, Suzanne Black didn't imagine that the reason some of her students struggled was because they didn't know how to read their textbooks. Black teaches the most advanced biology class available at her high school in Kenmore, Wash.

As the years passed, however, the problem became clear. "The longer I do it, the more I realize that it's hardest for the poor readers," she says. Today her strategy is different. "When a student is struggling in my class, the first thing I'll do is ask, 'Why don't you read me that paragraph?'" she says. "Often, they can't sift out the main details. They don't understand the organization of a paragraph, that the first sentence is a topic sentence, that the following ones are supporting details." So she shows them those things first.

Research backs what Black learned from experience. In one study of 1,651 high school students from three states, reading ability was just as important to students' science-class grades and scores on state-level science tests as the amount of science knowledge they had. The study found reading skill was even more important than such background knowledge for correctly answering questions based on passages about science.

Given the evidence, it is important to find the best ways to teach kids how to read science. "Learning how to learn science text and to be strategic about science text is different from learning to read English literature or things of that sort," says Kim Gomez, an educational psychologist at the University of California, Los Angeles. And "working with kids on science-text reading, in science class, is much more successful" than trying to do it in language arts classes, she says.

Research into techniques for mastering science text has evolved over a generation. Concept mapping was popular in the 1980s, for example. You might have made some yourself. They're those charts with the main ideas all written inside circles. Lines connect the circles and labels identify the relationships between the circles. A photosynthesis concept map might have "plants" and "photosynthesis" in different circles, plus a line from the first to the second labeled “make food by.”

Since then researchers have found several strategies that seem to be even more effective than concept mapping. In one compelling study researchers at Purdue University tested four reading strategies on 80 college students. One fourth of the students were told to type everything they remembered from a passage they read about sea otters. Then they repeated the read-and-type cycle. A week later those students recalled the sea otter info better than any other group, including one that made concept maps, one that reread the passage four times and a group that read the passage once.

Oddly, the students didn't seem to be able to tell which strategy would help them remember the most. When surveyed, they said they thought rereading would work best and that typing what they remembered would be the least effective. The study made it to the What Works Clearinghouse, a U.S. Department of Education database that aims to collect the strongest studies on teaching techniques.

In her research Gomez has seen other strategies that succeed for learning math and science, especially for kids who aren't reading at grade level or whose families don't speak English at home. Tops among them are annotation, T-charting and summarization. "Those are the strategies that we've used consistently and with a whole lot of success," she says.

Annotation sounds a bit like what is taught in language arts classes. Students use a set of symbols to mark in their books where they see different elements such as main ideas, supporting ideas, key vocabulary words and transition words. T-charting organizes ideas into two-column charts: topic sentences go on the left, supporting details on the right, for example. Summarization simply asks students to write down main points from what they just read.

Gomez and her team vetted those three strategies in a study they presented at the International Conference of Learning Sciences in 2010. They had 15 teachers in a Chicago high school teach all three strategies to about 860 students. The researchers then gave the students tests that asked questions about a passage on a science topic that hadn't been presented in class. Students were randomly assigned to use one of the three strategies. The students who used their assigned strategy correctly had the highest scores on their science tests, even when the researchers controlled for students who had better reading skills to begin with.

If kids have so much trouble reading science textbooks, why not ditch the textbook altogether and rely on lab work? For one thing, textbooks may be good for science learning. One recent study (pdf) found that among a representative sample of U.S. science students, those who said their science teachers had them read textbooks more often had higher test scores. Textbook reading wasn't all that was important, of course. The same study also found doing lots of hands-on activities was correlated with high scores. It seems sensible to continue using textbooks alongside activities, concluded the study authors, a team from the admissions test company Educational Testing Service. "In a best-case scenario having students read and process some passages from a text before they come to class enables me to conduct a discussion, to play with the ideas," Black notes. "It would be deadly dull if 100 percent of my class time was spent imparting information

The techniques may provide benefits beyond science class. "We have found in our research that the kids end up using the same sorts of strategies and skills in their other classrooms, like in social studies and then English language arts," Gomez says. Furthermore, the techniques may offer an answer to that old schoolkid lament about "When am I ever going to use this in the real world?" Says Gomez: "I think that textbooks are a nice prelude to the kind of reading an adult has to do when they're reading science articles in The New York Times or in their local newspaper and they're trying to make sense of the big ideas they're being presented."