This publication presents the reports from two studies, Math Online (MOL) and Writing Online (WOL), part of the National Assessment of Educational Progress (NAEP) Technology-Based Assessment (TBA) project. Funded by the National Center for Education Statistics (NCES), the Technology-Based Assessment project is intended to explore the use of new technology in NAEP. This publication is organized into two parts. Part I, Online Assessment in Mathematics, contains the report from the Math Online study. Part II, Online Assessment in Writing, contains the report from the Writing Online study. Each report is paginated separately. Appended to Part I are: (1) Inter-Rater Reliability; (2) Ease of Assessing Existing NAEP Framework Content Areas on Computer; (3) Students Omitting, Not Reaching, and Giving Off-Task Responses; (4) Test Mode by Population Group Contrasts; (5) Self-Reported Computer Experience; and (6) Student Mathematics Performance on Computer-Based Test and Paper-and-Pencil Test by Self-Reported Computer Experience. Appended to Part II are: (1) Sample Selection; (2) Understanding NAEP Reporting Groups; (3) Writing Online Hands-On Editing Tasks; (4) Writing Online Speed and Accuracy Tasks; (5) Background Questions Administered in Writing Online; (6) NAEP Grade 8 Writing Scoring Guides; (7) Statistical Procedures; (8) Percentage of Writing Online Students Who Report Using a Computer for Different Specific Writing Purposes; (9) Summary Statistics for Computer Familiarity Measures; and (10) Analysis of Variance Results Relating Computer Familiarity and Gender to Writing Online Performance. (Part I contains 42 tables and 22 figures; Part II contains 43 tables and 19 figures.)