Last day of Preschool

Today was Noah's last day of preschool. To celebrate, his class took a field trip to Columbian Park. It was actually really nice. I got to talk to some of the mom's that I have seen every Tuesday and Thursday, but have never really "talked" too. These are just two pics of the day. Why is that my son's best smiles only come out when he is holding a frog, tadpole, or in this case a worm?