This is not idiomatic. However, if you replace jumping with its synonym skipping, it becomes idiomatic. Alternatively, make it jumping over and it might not be how most native speakers would say it, but it would be understandable. This defect is not entirely surprising given that Polya was not a native English-speaker, and probably didn't even work mainly in the English language until late middle age.
What he means is that the student manages, through some stroke of inspiration, to see the solution without taking the expected steps of reasoning from the problem statement to the answer. As such, preparations isn't the best choice of word either, but his meaning is reasonably clear if you know the subject and the language well enough to figure out what he meant.
: Bearing in mind that synonyms are frequently not entirely identical in meaning.