This document provides guidance on using assessment data from AssessTrax to guide instruction. It outlines a 4-step process: 1) Decide which data to analyze, 2) Collect and organize the data, 3) Analyze it to identify strengths, weaknesses and trends, 4) Create an action plan. Key aspects covered include compiling answer frequency reports to identify concepts below 70% mastery, and using matrix reports to analyze student performance by question, objective or group. The overall message is that assessing, analyzing and acting on data helps ensure classroom instruction is effective.