A local middle school requested that the Water Center of Advanced Materials for Purification of Water With Systems (WaterCAMPWS), a National Science Foundation Science and Technology Center, provide an introduction to pH for their seventh-grade water-based service learning class. After sorting through a multitude of information about pH, a grade-appropriate, hands-on laboratory was developed. That lab, "Creating the pH Scale," has subsequently been used statewide by teachers, receiving positive reviews and a general consensus that it helps students grasp the fundamentals of pH. The lesson requires two to three days, depending upon the length of class periods. The general plan for instruction over three days is as follows: Day one: Introduction of water molecule, dissociation, and powers of 10; Day two: Hands-on pH testing of common household products using cabbage juice, a universal indicator; and Day three: Review of pH test outcomes, journal writing, conclusions, and inquiry extension activities. Each of these days is needed to incorporate factual information, laboratory work, and an element of fun. (Contains 6 figures and 4 online resources.)