ClassroomEvaluate & SampleCommon CoreCommon Core State StandardsEnglish Language Arts ProgramsGrades K–12 ELA Programs Grades K–12 Write Source Write Source® is the only K–12 print and fully personalized digital language arts program with complete coverage of the Common Core Writing, Language, and Speaking & Listening standards. This highly engaging program helps students master the key writing forms, writing processes, Six Traits, and grammar, usage, and mechanics skills through cutting-edge technology tools. Learn More Write Source® is a registered trademark of Houghton Mifflin Harcourt.