Here is a Cultural Literacy worksheet on gross domestic product (GDP). This is a half-page worksheet with three sentences and three comprehension questions. In spite of its brevity–or perhaps because of it, because the basic concept of GDP is simple–this is a good basic explanation of this broad measure of economic activity in a nation state, state, or province.
I would think this would be useful in just about any social studies class, but especially in the second half of high school.
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.