What is the difference between accommodations and modifications?

Accommodations change the how; modifications change the what.

An accommodation removes a barrier so a student can access the same grade-level content and be held to the same standard — extra time, a quiet room, text-to-speech, a scribe, or a calculator for a non-computation goal. The expectation is unchanged; only the path is adjusted.

A modification changes the expectation itself — fewer problems, a simplified text, a lower-grade-level standard, or different grading criteria. The student is working toward a different target.

The distinction matters legally and instructionally: accommodations keep a student on grade-level accountability, while modifications alter it. When you can meet a need with an accommodation rather than a modification, you keep the bar high while still giving access.