Elements combined or compared in a sentence should take the same grammatical form.
Consider the following sentence:
The problem is in the last part of the sentence, where the writer introduces a comparison between girls and boys. The two sexes are being brought up by the Victorians to live two different kinds of life. But the girls' education is described using the -ing form of the relevant verb (learning), whereas the boys' education is described using the indicative form (prepared). (The result, technically, is a comparison between a noun + adjective phrase - girls learning... - and a noun + verb, boys prepared.)
The sentence can be improved by changing the form of either verb.
Note that either change will make the sentence more effective by heightening the contrast between the boys' and girls' education. Keeping the grammatical structure the same on both sides of the comparison makes the words boys and girls stand out as the single important difference between the two sides.