The physical science big 20s are a set of year long questions used to determine mastery of standards. There are 8 different forms: A, B, C, D, E, F, G, H. I administer a big 20 every 3 weeks in my classroom. Each number on the big 20 is always about the same standard. For example, number 4 on every big 20 form is always a question about the periodic table. Students are expected to improve scores as the academic year progresses. Students graph their own progress in their interactive notebooks. They keep a real time line graph of their own data for number correct. I also have my students keep a standards correct graph, so that it is obvious according to the graph which standards have been mastered and which standards need more teaching/learning.