This lab, presented by the National Nanotechnology Infrastructure Network, introduces students to the difficulty to of measuring at the nanoscale. Accuracy and precision are the most important principles or measuring at such a small scale, and with the growing demand for nanotechnology careers, an understanding of nanoscale measurement is important.  In this lesson, students will the standards of measurement, as well explore the differences between "accuracy" and "precision" in a one class-time lab with circle and square templates, rulers, and an index of refraction plate. Included in this lab are: teacher guide, student guide, and measurement templates for the circles, squares, and ruler.