The origin of the terms uppercase and lowercase might seem pretty self-explanatory. Upper and lower must be references to the height of the letters, and the use of case is presumably an offshoot ...

Students would have to write upper and lowercase letters in cursive, write words and sentences legibly with proper spacing ...

(There are other allographs of the letter "G," including uppercase printed "G" and upper- and lower-case cursive "G.") “We think that if we look at something enough, ...