Threshold: Pre-GED covers the same content areas as the GED tests, in an open, user-friendly format. This allows adult learners to concentrate on the content they need to achieve high GED scores. Threshold addresses the demand the GED makes for focused core instruction that sharpens students' skills in reading, writing, critical thinking, and problem solving. Throughout each text, questions in GED format call upon the content knowledge and reading strategies that adult learners gain by using Threshold. Biology, Earth Science, Chemistry and Physics are presented in meaningful and relevant context to the adult learner.