In this activity, students use information from the Deep Sea Drilling Project to look for evidence of seafloor spreading in the Mid-Atlantic Ridge. Using temporal and spatial data obtained from core samples, students create and analyze a graph, looking for patterns in the data. Through graphical analysis, students should discover that the older a core sample is, the farther it will be from the ridge. This will be confirmed when students compare their graph to the map of drilling sites provided in the instructions. The lesson plan also includes analysis questions and ideas for activity extensions. This activity would take one or two class periods to complete.