This digest offers guidelines to help teachers prepare students with disabilities to succeed on state and district writing assessments. Teachers are urged to use the three principles of effective writing instruction: (1) use a basic framework of planning, writing, and revision; (2) instruct students in steps of the writing process and the features and conventions of the writing genre; and (3) provide feedback guided by the information explicitly taught. One methodology that follows these principles, Self-Regulated Strategy Development, is explained in terms of goals, the sequence of instruction, and methods of individualization. Teachers are also urged to prepare students for assessment (a mnemonic writing strategy called PLAN and WRITE is briefly described); to use assistive technology in instruction and testing (including software for transcription, planning, and communication); and to provide test accommodations, such as extending time limits, dictating to a scribe, or using pencil grips. (DB)