It turns out that the stuff our boy had left in his safe, secure locker at school was displaced. I got a frantic text and then call from the lad about 20 minutes after I dropped him off asking me to come get him, he didn't have his stuff and couldn't participate. I told him to hang tough; I had his back.
More to the point, I had his backPACK. We had bought a year's worth of school supplies, so binders, paper and other supplies were a piece of cake. We happened to have a spare backpack the County has given him in August, and his Chromebook could easily serve the role his table had played. I threw together what I could and raced it over there before first period was over.
The look he gave me as he shambled off towards second period was worth all of yesterday.
Update: The missing backpack has been located. His counselor called a couple of hours ago to give me the glad tidings.