Lightbrite…………..
sorry to burst your bubble BUT pencils come in other numbers besides 2. There are 2 different scales for lead pencils. One rates the hardness of the lead, the other the blackness of the impression.
Boys were required to take mechanical drawing and drafting in Junior High School when I attended and we used #2,3 and 4 both hard and soft versions.
Most exams read by optical scanners are designed for #2 pencils and instructions require their use, but the others exist.