I'm partway through watching The Imitation Game, the biopic about Alan Turing. In the scenes depicting Turing's childhood, Turing and Christopher exchange notes/letters, which they first encrypt to prevent others reading them.
The first message is passed to Turing by Christopher in class, before it's confiscated and thrown away by the class teacher, only for Turing to fish it out from the bin and then decipher it, as shown below:
The second is a short letter Turing is shown writing in his dorm room, before then encrypting it:
What methods are these two encrypted with, and therefore, how would they be solved? I realise they're probably stupidly simple, but you know, I'm dumb. :)
Also, as an optional bonus, there's the "Under 10 Minutes" crossword puzzle that the older Turing devises to recruit new Bletchley Park agents. It seems to be just a straight crossword, but it looks impossible to solve given that the handwriting of the clues is really tough to make out.