Where does he learn this stuff?

Conversation at school as reported by his teacher:

Setting

Classroom of 1st Graders. Teacher at board assigning "morning work." The children have to fill in the blanks of the sentence: ______ is good at _________.

Players

Child 1
Child 2
Teacher
Alan

Action

Teacher: What words do you think you could put in the blanks?

Child 1: Sammy is good at baseball.

Teacher: Great!

Child 2: Can I put "I" in the first blank?

Teacher: Does "I is good at" sound right? Is that how we talk?

Alan: It is if you are a hillbilly.