As the section head "Reaping" suggests, in this part of the novel the limitations of Gradgrind's utilitarian philosophy in raising his children comes to fruition. Lousia and Tom have been raised to devalue emotions or sentiment and to put their emphasis on money and practicality. As a result, Louisa is married to Bounderby, a man who is rich but loathsome to her, while Tom's lust for money and lack of moral compass lead him to rob Bounderby's bank, while framing the good and innocent Stephen for the crime. Both children end up miserable as adults because of the way they have been raised.

Louisa's lack of awareness of her own emotions and what they mean makes her seemingly easy prey for the bored Harthouse, who tries, but fails, to seduce her. As the section ends, Louisa, who has managed to escape Harthouse, collapses at her father's house, telling him of her miseries. For the first time, Gradgrind realizes that his method of education was a terrible mistake that has damaged his children. What the Gradgrind family is reaping is misery because they have chosen to ignore imagination and feeling, necessary components of a well-rounded life.

I can't speak to your expectations, as you will have to explore those on your own, but to my mind, Dickens lays the groundwork in the first section for the miseries Gradgrind's utilitarianism will produce in his children. Dickens is writing fiction for a popular audience and makes it amply clear that he does not approve of a world based solely on facts and figures. We could, therefore, have expected life to go wrong for Tom and Louisa.