Positives

• The resource can be downloaded and used offline or printed. 
• This activity could be implemented with real tree cores or disks as well.
  

Additional Prerequisites

• Ensure that students read the background information provided in the worksheet, as it will guide them in finishing the work.
• To have students cut the strips out, you will need to print out the worksheet and provide scissors.
  

Differentiation

• Consider an excursion to a location where trees have been felled to actually count the rings of the tree trunks.
• This activity can help engage students and provide a hands-on activity for learning about weather and climate.
  
• Similar resources include CO₂ in the Ice Core Record and Paleoclimate: A History of Change.