Seventh grade EXPO students tackled a very large question this semester. The question posed was to deconstruct the notion of time and what are the different ways we can we measure time. For many groups the notion of thinking outside the typical guidelines of time and how we currently measure time was a challenge as time can easily seem as a definitive unchanged unit that have always been used.

Students researched the different methods that humans have used to measure time. As a class we made observations about what all these methods have in common. When students had identified that all ancient clocks were using physical methods of change and placement to make their measurement we then had ground to begin our journey of creating our own clocks.

Students divided themselves into groups and then were tasked with using recycled materials to create their own type of physical clock. The students could use water or fine playground sand as the medium to move to mark their unit of time. Groups made drawings and predictions as to what might work best then they began diving into the materials to create a clock and a unit of time.

Over the creative process the students had to overcome the problem of consistent measurement. Once groups had a tool that was consistent within 5% on each timed trial they then had a working model to use. Groups then had to use their new unit of time to make calculations about how many of their units would fit into our standard model of time. This had many natural connections to mathematics and reinforcing many of the items they had studied this year.

The struggles along the way with regard to design, constancy and construction were some of the best learning moments for this class. Some groups easily excelled in one area where some groups struggled with very initial concepts such as how the sand or water might move.

Great job 7th grade!