Which types of sand timers did you find the most interesting?
What different purposes did the sand timers have?
Explain to the students that they are going to design a sand timer of their own, then use their knowledge and understanding of time to make it accurate.
Provide the students with a copy of the Math Investigation – The Sands of Time. Read through the scenario, the task and the procedure with the students. Answer any questions the students may have about the task and check that they understand the procedure.
Project some images of sand timers on the board. Discuss and analyze the designs used. Highlight some examples which have followed the standard design, as well as some examples which have not.
Provide the students with the necessary materials to complete the investigation. Monitor and support the students as they plan, construct and test their sand timers by following the instructions provided in the investigation booklet.
Reflect upon the investigation as a class by allowing the students to share their designs. Encourage them to describe some of the problems they experienced during the investigation and the ways in which these problems were overcome.
Encourage more capable students to increase the sophistication of their sand timer designs by adding additional elements.
Support less confident students by allowing them to consult with a teacher or teacher aide during the planning process.
Suggested Assessment Strategies
used strategic whole class or individual questioning
observed student participation during learning activities