My version of Baldi's backstory.
When Baldi was young he was terrible at math but would constantly be playing with the rulers he found around the classroom. He would be constantly called out for this by his teacher who would give him lashings with whatever ruler he had in his hand that day. Baldi had a very good sense of hearing so when he finally became tired of the abuse at school for his stupidity, he listened in on the lesson. He would become obsessed with the math his teacher would display so he would test other children's wits with almost impossible questions. When a child would get one wrong he would give them a lashing just like his teacher would to him. Growing up Baldi would do the same thing, even in his career which he still has today.