This activity, especially when repeated many times over the course of a month or year, helps students connect with the ecosystem around them and observe changes to the natural world. Many different versions of this activity exist, but we love this one from Pacific Education Institute!
https://docs.google.com/presentation/d/1Tc8KSJR-jmdfZFVaG_A06YXiqSI21Eoo2rqK4dKSRXo/edit?usp=sharing