The Composite Is Three Sections

Each of the four multiple-choice sections gets its own scale score from 1 to 36. The Composite takes exactly three of those scores, English, math and reading, adds them up, and divides by three. Science sits outside this calculation entirely. That's not an oversight: the Composite was defined this way from the start, and science was built to feed a different reported score instead, one that tracks STEM performance on its own.

This is why a flawless science score can leave your Composite untouched. If English, math and reading stay the same, their average stays the same, no matter what happens on science. The three sections that count are fixed, not whichever three (or four) you happened to sit for that day. Skipping one of the required three doesn't let the other two cover for it either: a blank section often scores at the bottom of the scale, and that low number still gets averaged in, dragging the Composite down hard.

Seeing the Composite as a simple three-way average clarifies why section strategy matters unevenly. A weak math score pulls just as much weight as a weak reading score, since each is one-third of the same sum. Understanding this split also sets up how the separate STEM score and any other combination scores work: they borrow from these same four section scores but combine them under different rules.