AP Calculus Guys Got a Surprise on Monday!

Last week I reached out to the parents of the students in the AP Calculus class and asked them if they would be willing to participate in a surprise for their son's math class.  Of course they were all quite enthusiastic!
So, last Friday afternoon, my kids and I set out on a Tour de L'Isle so to speak.  We went to the home of each student and delivered a medium sized, sealed envelope to each parent, who was directed to keep it hidden and secret from their son until he eventually came and asked for it.  
All the students knew, was that there would be a surprise on Monday but no other details were given.  Surely, they were anticipating another guest speaker.
So on Monday morning, I began our Zoom session by telling them how busy my kids and I were the Friday prior.  I then proceeded to show them pictures of us outside each of their homes with their parent! The boys were shocked to see that I had one, gone around to each of their homes, and two that I did so without any of them catching us!
On my say, they were each sent to find one of their parents and ask them for "their envelope".  They were instructed to bring the envelope back to the Zoom WITHOUT opening it.  After some wild guesses, they were allowed to open their envelopes.  They cracked up when they discovered it was two pieces of glittery sidewalk chalk.
What followed was an explanation of their final assignment for the term:  They could choose between Sequences/Series or Linear Algebra, the two major topics we covered after writing the AP exam in early May.  They were then given a randomly assigned question which they would need to solve using sidewalk chalk on their driveway/street/sidewalk/wall of their house (parent permitting of course).
The attached pictures capture not only their incredible math skills but the enthusiasm and pride that accompanied it.
Never too old for glittery sidewalk chalk.  Well Done, Boys!

-Samara Sayegh, Math Teacher