Godfrey Rangasammy, a supervisor of science, background center, and Tanisha Johnson, a science coach, observe a chemistry class at Northwestern High School in Hyattsville, Md. (Astrid Riecken/For The Washington Post)

The chemistry students at Northwestern High School were not fiddling with Bunsen burners or studying the periodic table one recent weekday morning. They were sitting at their desks, reading an article about food coloring, underlining key ideas and preparing to analyze it in an essay.

This is the beginning of what Prince George’s County officials hope will be a significant shift in teaching and learning, one that mirrors a change taking hold in high schools nationwide as districts adjust to the Common Core State Standards. Literacy, long the responsibility of English teachers, is filtering into every other classroom — including math, science and even health class.

The idea is that in order to be ready for college, students need more explicit instruction about how to read, think and write analytically. And they need to be able to glean meaning not just from literature in English class but also from historical primary sources, scientific articles and other (sometimes dense) works of nonfiction.

Prince George’s has started an ambitious effort to train all teachers to be literacy teachers, and lots of adults in the system are hopeful: “I think it’s going to be effective in the long run if all teachers buy into it, if they believe that it can work,” said Sheree McNeil-Gordon, the teacher in that Northwestern High chemistry classroom.

All students aren’t buying it — yet.

After observing a chemistry class,history teacher Jessy Feinberg, 24, writes down notes of her findings inside a conference room at Northwestern High School. (Astrid Riecken/For The Washington Post)

“English and science are two different things,” said Bella Kuete, 15, one of McNeil-Gordon’s students, who said she’d never been asked to write much in science class. “Writing an essay doesn’t help me get better at science.”

Teaching literacy in classes other than English — or “reading and writing across the curriculum” in education lingo — is often implemented unevenly, in fits and starts and without much quality training for teachers.

Proponents of the Common Core hope that the new standards, which have been adopted by more than 40 states, will trigger a new and sustained focus on literacy in all subject areas. The Core requires students to analyze what they’ve read and to write arguments with clear thesis statements backed by evidence; the introduction to the standards say that they “insist that instruction in reading, writing, speaking, listening, and language be a shared responsibility within the school.”

“The focus on college- and career-ready standards has really given us a call to arms that we’ve got to prepare our students in another way, not just with the facts that are associated with a particular content, but with the ability to think, read and write in that content,” said Jayne Ellspermann, a Florida high school principal and president-elect of the National Association of Secondary School Principals.

In Prince George’s County, overhauling literacy instruction is the centerpiece of chief executive Kevin Maxwell’s aggressive plan to improve achievement, with the goal of ensuring that by 2020, 90 percent of students are graduating from county high schools prepared for college or the workforce.

“Literacy is the key to everything else in school, and that’s why our strategic plan is centered around it,” Maxwell said Thursday evening in his annual state of the schools speech, according to a copy of his prepared remarks. “It permeates every aspect of our work and it is our most effective tool in closing the achievement gap.”

At the elementary-school level, the literacy push means doing more to make sure that children are able to read fluently and comprehend on grade level. At the secondary-school level, the school system is training teachers at every school to use common terms and strategies.

Students are learning to “annotate” whatever they’re reading, marking it up to highlight key ideas and words that they do not understand. They are learning to “unlock the prompt,” or make sense of multi-part essay questions. They are learning to build thesis statements and discuss rhetorical devices.

Northwestern history teacher Jessy Feinberg said she thinks there is great power in giving students consistent messages from classroom to classroom. Social-studies teachers were the first to be trained this fall. Then came science. Next is math, arts and health, technical education and world languages.

“I love the idea that my kids can go from one place to another, and it sounds familiar,” Feinberg said. “Our hope is one day, we won’t have to tell them to annotate a text, they’ll just take out a highlighter.”

The model for Prince George’s County’s effort is Brockton High in Massachusetts, which famously skyrocketed from one of the worst-performing schools to one of the best-performing in the state after implementing common literacy strategies across all subject areas.

Prince George’s has overhauled teacher professional development to focus on literacy, and every school has teachers and administrators who are tasked with leading the charge to change. Six schools — including Northwestern in Hyattsville, Md. — have literacy coaches providing full-time support to teachers inside and outside of their classrooms. The school system hopes to double the number of coaches next year.

That level of support is particularly important at a school where teachers face challenges in delivering grade-level material because their students are behind academically. Adding another set of responsibilities can be stressful.

“Part of my job is building relationships and easing the pain of being a reflective school district making shifts and attempting to be better,” said Rashieda Gantt, the literacy coach at Northwestern.

About 73 percent of Northwestern’s students are economically disadvantaged, and 24 percent are learning English as a second language. Just 17 percent were proficient in English, according to new Common Core exams administered for the first time in 2015.

John Delaney, an Advanced Placement Biology teacher at Northwestern, said his students last year were relatively weak on the writing portion of the AP exam, and they had trouble finishing multiple-choice questions on time. He’s hopeful that the schoolwide focus on literacy will help his students do better this year.

“The ultimate payoff is on the AP exam. If they do well on the exam, then they’ve saved themselves money and time in college,” he said.

Shawn Joseph, deputy superintendent in Prince George’s, said the district recognizes that the shift it is undertaking is massive and will take time. District officials are examining its curriculum and looking for things that can be cut out to make more time for teachers to focus on literacy.

“We’ve dramatically raised the level of expectation, and if we don’t raise the level of support in schools, there’s going to be extreme frustration across the board for teachers and students,” Joseph said. “The good news is that there’s a momentum in the district that has not been here.”