Project Almanac is a 2015 American found footage science fiction film directed by Dean Israelite in his directorial debut, and written by Jason Harry Pagan and Andrew Deutschman. The film stars Jonny Weston, Sofia Black-D'Elia, Sam Lerner, Allen Evangelista, Virginia Gardner and Amy Landecker. The film tells the story of a group of high school students who build a time machine.

Filmed in 2013 and originally planned for an early 2014 release, the release date was later moved to January 30, 2015. Upon release, Project Almanac received generally mixed reviews from critics and audiences, and grossed $33 million against a production budget of $12 million.

High school senior and aspiring inventor David Raskin is admitted into the Massachusetts Institute of Technology, but is unable to afford its exorbitant tuition. Upon learning his mother, Kathy, will be forced to sell the family's house, David enlists his sister Christina and his friends Adam Lee and Quinn Goldberg to search through the belongings of his father Ben, an inventor who died on David's seventh birthday, in the hopes of finding something David can use to get a scholarship, filming themselves all the while.

He finds an old camera with a video recording of his seventh birthday party, in which he briefly spots himself (at his current age) in a reflection. Noting how he appears to be reaching for a basement light switch in the reflection, David and his friends enter the basement, which his father had forbidden.

The group pull the switch, activate a trapdoor, and find blueprints for a time travel device that Ben was developing for a project called "Project Almanac" for DARPA, a government agency, which allows them to build a functional time machine. They successfully send a toy car back in time, but cause a blackout in their neighborhood. When they get noticed by David's crush Jessie Pierce, whose car's fuel cell they use to power the device, they recruit her into their experiment.

The expanded group travel back to the day before and break into Quinn's house, where he draws on the back of his sleeping past self's neck, but the past Quinn awakens, causing a feedback loop that nearly erases them both from the timeline. Following this, they agree to use the machine for personal gain on the condition that they don't time jump solo. At first, the machine's capacity would only allow them to time jump three weeks into the past at most, so they test it further by giving Quinn another chance to succeed at his science presentation, Chris getting back at a bully, as well as winning the lottery (though they actually end up winning the second place prize due to Adam's writing a wrong number). While at Lollapalooza three months prior, David hesitates to declare his feelings for Jessie, causing their relationship to become awkward, so he travels alone back to Lollapalooza to change that, leading to a future in which they are a couple.

When he returns, he finds that the blackout they caused in the first experiment resulted in their school's star basketball player getting hit by a car and breaking his leg, which in turn caused the player's pilot father to crash a commercial airliner, among other global catastrophes. David goes back alone to save the player and avert the plane crash, only to discover that Adam was hospitalized and in a coma after a car accident.

David continues to travel back in time alone to rectify the accidents, but Jessie catches him during one of his trips and accidentally sends herself back with him. She confronts him, and David admits to using the time machine to win her affection. As Jessie lambastes David for his deception, her past self appears, causing a feedback loop that erases Jessie from the timeline.