The biggest issue with this is that the first sentence is run-on, you should consider breaking it into smaller sentences, maybe by getting rid of the "and" after describing the mother, replacing it with a period and letting the father get a sentence of his own. Also, you could try "-on how happy the Railway family is. The story also uses detail on how nice the parents are-" something along those lines, just to break the run-on sentence?
This is minor, but at the end "creates a sense of perfection, by describing their house-" the comma before by isn't necessary, and can either be deleted, or you can rephrase like "a sense of perfection. The story does this by describing-"
because tina was telling the class about her and her group fought in history class & sarah said to herself sounds boring which means that tima heard it and turned around angrily because of what sarah said & that was the main conflict