This lesson is designed at three different levels. Each is mainly after the students being able to determine the speed of the Earth around the Sun.
Basic Version The basic version introduces the task directly. Students find some information online.
Advanced Version The advanced version asks students to reason through the problem before searching online. The outcome is the same.
Physics Version This version suits students familiar with universal gravitation and circular motion.
https://www.youtube.com/watch?v=uZ9iNsjyw7k&feature=youtu.be
This video discusses common difficulties experienced during this activity in the past.