Thousands of students use Sterling Test Prep to achieve academic success! Targeted and comprehensive review of organismal biology topics covered in college biology. Thousands of students use Sterling Test Prep to achieve academic success! Targeted and comprehensive review of organismal biology topics covered in college biology. Since 1991,  Sterling Test Prep  prepares students for academic success. Sterling Test Prep  publishes more than 140 study aids for high school, undergraduate, graduate, and professional students. Our writers, contributors, and editors are highly educated in sciences and humanities, with extensive classroom teaching and research experience. They are experts on preparing students for standardized tests, as well as undergraduate and graduate admissions coaching.