This is my standard based grading/mastery learning model.
This document breaks down a traditional unit on rocks and soil formation into a few key ideas. They are written as student centered deliverables. There are a variety of assessment types in each unit, and student choice is encouraged.
An example: I will identify the impact of desertification by analyzing a primary source.
1. Identify a location on Earth currently experiencing desertification. List 10 impacts (environmental, economic, or ecological) due to desertification.
2. Write a 5 entry blog from the point of view of a farmer experiencing desertification.
3. Make a list of 5 foods that grow in arid areas, and 5 that grow in tropical areas. Then identify where they are currently being grown, and how that would change.
Students choose one option to complete to demonstrate mastery. Other standards may be assessed through quizzes, lab activities, presentations, or design challenges.