As a senior physics II student in high school in 1974, my physics prof came in with the FIRST digital calculator available in any San Antonio high school. Maybe the firsdt in the city as well.
In fall 1976, after two years of using a slide rule for engineering classes, I scraped up 435.00 dollars (in pre-Carter inflationary dollars!) for an HP45 to use as a junior and senior. RPN.
The first calculator I ever saw was at Troy in, I think 1972, it might have been 71. A psychology prof, newly hired said he was surprised to find the department had an electronic calculator. He said they were very expensive.
It was so exotic that it made no impression on me. He passed it around for all the class to see and handle. I have no idea what the functions were. It was about the size and shape of a book.
I remember using those TI calculators with the trig functions, the best ones had a switch to select deg/rad/grads. I didn't own one, the kids who had one (at least two of them planned to pursue engineering degrees) shared them with those of us who didn't.