This kid is bananas, B-A-N-A-N-A-S
We often expect children to be open and honest about their emotions. They throw tantrums when they’re angry. He posted a photo of the bananas to Twitter, explaining that his son had left the half-opened bananas for him to find after they had a disagreement. It’s a surefire way to get a parent’s attention while also getting the last laugh.
Check the folder(s)
This appears to be a shared computer or drive, where he created a slew of numbered folders with file names that make up entire letter phrases. His sister, whom he accuses of stealing $20 from him, receives the letter. He hid her project in one of the 16 folders, each with its own set of subfolders, as a retaliation.