Here are some examples of the many OER textbooks available for economics. Search for others in the repositories linked on the left, or contact a librarian to help you find what you want.
Beginning with the details of an unnamed country, this interactive exercise lets students combine various economic policies to analyze their future impact (in the following two years) on the main macroeconomic indicators.
CORE is a global collaborative project in economics. It's empirically motivated and illustrated: students learn models motivated by facts from history, experiments and data. This full curriculum includes textbook, quizzes, and lecture slides.