From Deborah Meier, natch:
From 5-year-olds to 13-year-olds everyone studies the same subject matter at the same time. (A few years ago the staff added a short "spring fling"—to enable teachers to spend a month on a topic of their own classes' special interest, as well a Friday K-8th grade elective program that functions outside the set course of study.) The year is divided into trimesters; every winter it's one of four Ancient Civilizations; in the fall and then spring everyone studies a common scientific theme and an American history theme. These themes repeat every four years—so that each child studies the same "topic" in K-3, and again in 4-7. We "do" American politics each presidential election year, and we rotate between the natural and physical sciences. The other three American studies themes include the African-American experience, the Peopling of the Americas, and How We Make a Living. In addition we teach math and literacy both separately and as part of our thematic studies. All but the 8th grade are multi-age (K-1, 2-3, 4-5, 6-7), and every student (with the help of his or her own faculty adviser) must complete six portfolios (bodies of work) to the satisfaction of their graduation committee before walking across that stage in mid-June.