nothings wrong in english, what you said seems pretty decent if you expanded upon it correctly. I said his back was to the books - ignorance, and that gave the implication he could 'push' the books over -> what this symbolises etc.
I said something like this too, for the first image.how he had his back away from that big pyramid of books, which also symbolized all the information/knowledge he was missing out on.
Anyway, for the second slide, I said it was ironic, cause the boy went to buy the book, not borrow it yet he only had a 'good six months' to read it?
Didn't analyse any of the Harry potter stuff, didn't have timeeee for it.
And yeah , I just mentioned the slides as visual slides.