This toolkit is designed to guide educators in developing and improving practical measurement instruments for use in networked improvement communities (NICs) and other education contexts in which principles of continuous improvement are applied. Continuous improvement includes distinct repeating processes: understanding the problem, identifying specific targets for improvement, determining the change to introduce, implementing the change, and evaluating if and how the change led to improvements. This toolkit is intended for a team of educators who have already identified specific student learning needs and strategies to improve instruction to address those needs and are ready to test these strategies using continuous improvement processes. The toolkit aims to help the team with the final step in the cycle, which includes collecting data to measure implementation of changes and intended outcomes and using those data to inform future action. Measures for continuous improvement should be closely aligned to student learning goals and implementation of instructional strategies driving the continuous improvement effort, and they should be practical to use in a classroom setting. A team of educators can use this toolkit to proceed through a series of steps to identify what to measure, consider existing instruments, draft instruments, evaluate and refine instruments, plan data collection routines, and plan for data discussions to interpret the data and inform action. Regional Educational Laboratory (REL) Southwest developed the resources in the toolkit in partnership with the Oklahoma State Department of Education team working with the Oklahoma Excel NICs.