According to NCTM's "Principles and Standards for School Mathematics" (2000), the act of estimating is reflective of students' mathematical intuition and number sense. Students with more developed number sense are better able to judge the reasonableness of their results. To promote estimation, Jennifer Marshall explored incorporating images from the Estimation180 website into lessons with my seventh-grade students (www.estimation180.com). When using this free website, students are presented with real-world photographs and asked to use their mathematical intuition to make predictions about some aspect of the image. Marshall created a series of short estimation tasks to encourage students to reflect on the reasonableness of their estimations by using benchmarks to identify predictions that were too low and too high. The purpose of this article is to present these tasks and describe students' responses to them. In these tasks, students made estimates about percentage and angle measurements in photographs of partially eaten pies. They had multiple opportunities to view and discuss their peers' work to help them reflect on the variety of strategies they could use for future estimating tasks. Finally, students practiced using a benchmark strategy to improve their estimation skills.