''Life As We Knew It'' is a SpeculativeFiction [[YoungAdultLiterature teen novel]] by Susan Beth Pfeffer, told from the point of view of a teenage girl named Miranda Evans in the form of her diary, which she begins writing in [[NextSundayAD May of an unspecified year]]. Initially, things are normal, and Miranda is looking forward to the upcoming prom and her dad and stepmother have told her that they want her to be the godmother of the child they are expecting. Everyone is eagerly anticipating an interesting astronomical event: an incoming meteor that is supposed to crash into the moon. Miranda just looks at it as another excuse for extra homework assignments. However, most people are looking at it as a once in a lifetime chance to see an event like this. Miranda's mother has even baked cookies in honor of the occasion. But no one anticipates the moon being knocked closer in orbit to the earth and the havoc it causes. The climate is drastically altered, the coastal areas are hit with tsunamis, the supermarkets are closing as food runs short, the price of gas has risen to over ten dollars, electricity is no longer a guarantee, and the lists of the dead are expanding. It's TheEndOfTheWorldAsWeKnowIt, though no one wants to admit it.

The author of this series says she was inspired to write the first book in the Moon Crash Series, ''Life As We Knew It'', by watching ''Film/{{Meteor}}''. She says "it got [her] thinking about how the people who have the most to lose if [[TheEndOfTheWorldAsWeKnowIt the world comes to an end]] are kids" and wanted to write about how kids would cope with this particular scenario. There are three other book in there series, which are:

* ''The Dead and the Gone'', told from the point of view of Alex Morales, a young Puerto Rican teenager living in New York City dealing with the meteor strike. Both his parents are immediately killed in the incident, and it's up to him to protect his two sisters and find the food to support them.
* ''This World We Live In'', where Miranda is reunited with her father and step mother, who have brought Alex with them. The two get together while dealing with the stresses of survival, and toy with the idea of moving to a recovered city.
* ''The Shade of the Moon'' Miranda's brother, Jon, lives with his step mother and half brother in a city populated by those with skills that helped them whether TheEndOfTheWorldAsWeKnowIt, while dealing with old guilt and the knowledge that most of his family is forced to live in the slums for those who aren't as useful.

!!This series includes the following tropes
!!Tropes in ''Life As We Knew It''
* AdultFear
* AfterTheEnd
* AntiClimax
* TheApocalypseBringsOutTheBestInPeople: When she realizes that things will most likely get worse after the stores are being mobbed and sold out, Laura gets serious with enlisting her children's help with getting as much stuff and they can. Inverted, though, when she also goes against her usual charitable nature and refuses to give supplies to the local drive to get supplies for needy people in New York and New Jersey, though it's justified, given that the danger in giving up supplies that might be necessary later on as well as giving any hint that you have plenty for others to steal. The whole family goes to great lengths to ensure each other's survival.
* ApocalypticLog: Miranda's diary.
* AuthorAvatar: Miranda's mother
* AuthorFilibuster: It's apparent that the author is anti-Bush and hates Fox News.
* BirthDeathJuxtaposition
* [[spoiler:BittersweetEnding]]: TheEndOfTheWorldAsWeKnowIt has happened, [[spoiler:Megan, Peter, and Mrs. Nesbitt have died]], it's questionable at best whether or not [[spoiler:Miranda's dad, stepmother, and half-sibling are alive]], [[spoiler:the whole family is starving]], and [[spoiler:it's clear that things will never get back to normal]], but [[spoiler:Miranda's mother and siblings are alive, Miranda herself has lived to see her 17th birthday, her whole family is getting a massive amount of food, and it genuinely looks like they're going to make it through the winter]].
* BrattyTeenageDaughter: Miranda, the 16 year old heroine, starts out as this, but of course [[TheApocalypseBringsOutTheBestInPeople the apocalypse brings out the best in her]].
* TheCaretaker: After [[spoiler:ThePlague hits, Miranda is the only member of her family who doesn't get sick]] and goes to great lengths to ensure [[spoiler:her family's]] survival.
* CliffHanger
* ColonyDrop: Subverted. Earth itself suffers no direct impact.
* CoolOldLady: Mrs. Nesbitt
* ComingOfAgeStory: Miranda starts out as a BrattyTeenageDaughter who is mainly concerned about herself and then TheEndOfTheWorldAsWeKnowIt happens and [[TheApocalypseBringsOutTheBestInPeople brings out the best in her]]. Her mother even lampshades this by correcting herself when she tells Miranda what a special girl she is to tell her what a special ''woman'' she is.
* CorruptChurch- Miranda's former best friend, Megan, turns to God after their friend dies (before the book starts). The church tells her not to eat and she [[spoiler: dies of starvation]]. It is also revealed that the priest at said church was [[spoiler: taking food from his church members]].
* CrazyPrepared: The sheer amount of stuff they got really comes in handy when things get rough in the winter.
* {{Cult}}: As the world is ending, religious people are not only flocking to Reverend Marshall's church out of understandable panic, they're spending almost all of their time there, and even ''sleeping'' there. Megan says one day that it's the first time she's left the church in a while and that they only sleep for one or two hours at a time so they can keep praying.
* TheDiseaseThatShallNotBeNamed: It's only said that Becky was sick before she died, but it can be discerned from details in the narration that Becky died of cancer.
* DrivenToSuicide: [[spoiler:Megan's mother]] after [[spoiler:Megan herself]] has died.
* TheFundamentalist: Megan has come to be obsessed with church and following the doctrines of Christianity. She becomes even more so to a frightening degree after things get worse.
* GoodGirlsAvoidAbortion: Even when the apocalypse is going on, apparently.
* HollywoodAtheist: Miranda
* IllGirl: Miranda, Sammi, and Megan's friend [[PosthumousCharacter Becky]].
* {{Irony}}: In one of Miranda's dreams, she sees an old teacher of hers, who tells her "don't be careless" as he always told them when doing schoolwork... before he died running a red light.
* MarriedToTheJob: Dr. Peter Elliot; especially [[TearJerker sad]] when [[spoiler:he dies trying to heal people at the hospital.]]
* NoCelebritiesWereHarmed: While the president is never named, it's pretty obvious that he's supposed to be GeorgeWBush, what with Laura calling him an idiot whenever they hear of him.
* NoPeriodsPeriod: Averted. Miranda's mother tells Mrs. Nesbitt to get lots of Tampax for herself and Miranda. Miranda also makes note in her diary of having her period when she gets it. [[spoiler:Miranda also doesn't get it for quite a while when their food supplies run particularly low, [[FridgeBrilliance and this is most likely a hint as to how badly she is starved]].]]
* NobodyPoops: Averted. One of the major concerns is how to deal with everyone's bodily wastes.
* PathOfInspiration
* [[spoiler:ThePlague]]: Along with the other things going on, this happens.
* PosthumousCharacter: Becky, a friend of Miranda, Sammi, and Megan's before she died of cancer.
* ReallyGetsAround: Sammi.
* RetailRiot: Miranda uses a shopping cart to attack a woman who is trying to steal a food item from Mrs. Nesbitt.
* ScavengerWorld: the United States is on its way to becoming like this.
* SinisterMinister: Reverend Marshall is unquestionably corrupt. As TheEndOfTheWorldAsWeKnowIt gets progressively worse, people flock to his church in religious panic and even give him their food. Reverend Marshall accepts the food, even though the people giving it to him are starving and in need of it, and he is only too happy to tell Miranda about how he deliberately didn't bury [[spoiler:Megan's mother]] just because she was [[DrivenToSuicide a suicide]].
* SnowedIn
* TeenPregnancy: Laura is very worried about this happening to Miranda and does not want this to happen to her. Justified as Miranda having a baby would mean a threat to the whole family's survival.
* TooDumbToLive: With people dying and leaving left, right and centre, you would think the Evans family would check the empty houses for supplies. They might hold respect for the dead, but still.
** In the third book, they do start house raiding, and it's implied that they didn't before because of Laura's scruples, or that other raiders would fight them for it. When they do empty their neighbour's house they are super cautious about it.
* ToughLove: Laura shows this toward all of her children, making very little effort to soften the reality of the apocalyptic scenario around them.
* TraumaCongaLine: Little by little, Miranda's life gets worse.
* TwoFirstNames: Peter Elliott
* VisitByDivorcedDad

!!Tropes in ''The Dead and the Gone'':
* ApocalypseAnarchy: Stealing from corpses on the street to get food on the black market.
* DeceasedParentsAreTheBest: Alex's parents are presumed to be dead at the beginning of the story, though nobody really knows for sure.
* GraveRobbing- Kevin and Alex steal belongings from the dead people lying around in the city. They trade the stolen items in for cans of food.
** RobbingTheDead: Julie is appropriately horrified when a man [[DrivenToSuicide falls to the sidewalk]] right in front of them and Alex immediately starts looking for valuables when the man isn't even dead yet.
* IllGirl: Bri gets adult-onset asthma after volcanoes cause the air to be full of ash.
* SnowMeansDeath: [[spoiler: Kevin is killed during a snowstorm by a tree branch]]
* TooGoodForThisSinfulEarth: [[spoiler: Bri]]
* TheUnfavorite: Alex dislikes Julie for most of the book.
** However, towards the end of the book and all through the next one, he is shown to be fiercely protective of her and obviously loves her very much. This is most likely because Julie undergoes great maturity throughout the story (which means she is no longer the brat Alex disliked so much) as well as her being [[spoiler: the only family Alex has left.]]

!!Tropes in ''This World We Live In'':
* MercyKill: [[spoiler:Miranda kills Julie in her sleep once her neck is broken in the storm, her brother is missing, and the family isn't sure how they're going to survive in the aftermath of the tornado.]]
* SuddenSequelDeathSyndrome: [[spoiler:Julie breaks her neck and is quietly smothered.]]
* TrailersAlwaysSpoil: In the summary given in the jacket notes, it mentions that a tornado devastates the town, an event that doesn't happen until the book is nearly over.

!!Tropes in ''The Shade of the Moon'':
* ChildlessDystopia: While teens and older children are thriving now, there are a lot of people who didn't survive the initial chaos of the moon changing orbit. The current living conditions in the country also reduced a lot of peoples odds of conceiving. Gabe is one of the few small children in the enclave, and Miranda is one of the only pregnant girls for miles. Lisa worries that she may be booted from the enclave just because someone who wants a child expects her to leave Gabe with someone who could provide for him, and [[spoiler:Miranda is told her child died within minutes of it's birth so it could be given to a influential family that couldn't conceive.]]
* DateRapeAverted: [[spoiler: Jon tried to have sex with Julie before she broke her neck, and the injury resulted from her fleeing him.]] He tries to justify it by saying it would have been a NearRapeExperience if she'd only made it clear she didn't want it, but in the flashback he pretty blatantly ignores that she didn't, and insists on believing she was only afraid of what [[spoiler: Alex would think.]]
* FantasticGhetto: The grub towns, where anyone who wasn't important or didn't posses a valuable skill ends up.
* FromBadToWorse: Things are disfunctional, but bearable for most prior to the soccer game with White Birch. When Tyler takes advantage of one of the grub players suddenly dying to unfairly win the first game the enclave had a chance of losing, a riot breaks out, resulting in the deaths and disappearances of several hundred people. [[spoiler:Laura is among them.]]
* MyGreatestFailure: [[spoiler:Jon and Julie were safe when the tornado first hit. But then Jon scared her out into the storm.]]
* SuddenSequelDeathSyndrome: [[spoiler:Laura is hung in front of the White Birch school and shot when she tries to keep her students from being taken away after the riot. Lisa later shoots herself and leaves a suicide note with false information to keep anyone else from being suspected when they steal Miranda's baby back.]]
* UrbanSegregation: The enclave has air purification systems in it's buildings, food, decent education, and though everyone old enough to work does, most of the jobs are pleasant. The surrounding towns are filthy, and dangerous. The people living there work long, hard hours and get very little pay. There is only as much food as in necessary, the air is filthy, and not a single building can be locked.
* WantsAPrizeForBasicDecency: Sarah is the only kid in the enclave who seems to realize that being less privileged does not make a person inhuman. Jon, most of whose family is less privileged than himself, cannot say the same, but still acts like he's better than many of the other clavers.