February 07, 2019
January 17, 2018
Calvin mispositioned the board, making it a fulcrum (allowing Hobbes to do what he did). As he passes the boulder, the other end of the board will simply move down (think see-saw) and Calvin would not be launched into the air at all.
Therefore, the boulder should support the end of the board, not the middle.
Sorry, physics geek here :-P