From the College Board:
In May 1998, 5,163 students took the first AP Environmental Science Exam. The exam covers a onesemester introductory college course in environmental science with laboratory.
The questions included in Section I are designed to cover the breadth of students' knowledge and understanding of environmental science. The four questions in Section II consist of one dataset question, which requires students to analyze and interpret given sets of data; one documentbased question in which students answer questions related to a given document (such as a pamphlet, advertisement, or newspaper article) and apply their knowledge of environmental science to contexts that are current, relevant, and authentic; and two synthesis questions, which are indepth, often multipart essays.
Advice
The exam that you will take at the end of the course is made up of 100 multiple choice questions and four free response questions. Bring a small clock or wrist watch to carefully monitor your time. The exam is three hours long, one and one half hours for the multiple choice section and the remaining one and one half hours for the free response. The multiple choice section is worth 60% of your score and the free response makes up the remaining 40%. The number of questions on each topic is based on the percentages noted after the major topics list in the AP Environmental Science Course Description.
Note from test grader about math on exam:
"A student must show all their work on the calculations FRQ, but is not required to solve the problem using factor/unit analysis. They DO, however, need to label their units in their calculations. And this may seem somewhat odd, but frequently they do not have to actually label the units in their final answer if those units were specified in the question itself. And some students will solve the entire problem in narrative format  still counts!
Since no calculators are currently allowed on the APES exam, most of the calculations are generally in factors of 10 and if a student can simply use scientific notation they are far ahead of the game. But we have still have students write in dozens of zeros on their exam and get the correct answer  the readers don't care for that simply because we have to "count" all those zeros to make sure the student was using the correct number ;). And it helps if students know the numerical meaning of prefixes like "mega" or "kilo".
And on a related topic  there is no double jeopardy on the calculation problem, so if a student calculates an incorrect response to section "a", but then uses that incorrect number "correctly" in subsequent calculations, they will still receive points for those sections of their response. You can imagine how much fun grading those paper can be. And it also explains how a student can run a complete power plant for a year on less than ten pounds of coal and still receive the point."
