Formative evaluation takes place throughout an entire unit. It takes place in all five steps of the Problem Method.
Sample One-Sheet-Record-On-A-Clipboard
Summative evaluation takes place at the end of a unit. A specific time is set aside at the end for a comprehensive examination of what has been accomplished. The final evaluation has three parts.
1. Evaluation of the students by the teacher
2. Evaluation of the unit by the students
3. Evaluation of the unit by the teacher
Testing and Evaluation of Social Studies Students
http://www.socialstudies.org/standards/positions/testingandeval.html