Her other films include Aquamarine (2006), Return to Halloweentown (2006), Sydney White (2007), Superhero Movie (2008), The Last House on the Left (2009), The Innkeepers (2011), and The Front Runner (2018).

[11] In a 2009 interview with Teen Hollywood, Paxton disclosed that she had been accepted to several colleges, but decided not to attend any schools in favor of pursuing her acting career.

In 2003, Paxton starred in R. L. Stine's Haunted Lighthouse, a short 3D film attraction that still plays at several theme parks across the United States.

Paxton's first major role was in the teen film Sleepover, which opened in July 2004 to negative reviews and low box-office revenue.

[15][16] During the same summer season, she appeared in several episodes of Summerland, playing Sarah Borden, a mentally troubled teen who experimented with drugs and sex with Jesse McCartney's character.

In 2005, Paxton spent three months[9] working on the Florida-themed Aquamarine, in which she played the title character as a mermaid, opposite Emma Roberts and JoJo, whom she befriended while filming.

[9] Her debut music CD, The Ups and Downs, featuring the titled single "Here We Go Again," was due for release by Epic at some point "in the future"; as of March 2007, Paxton has not completed work on it, and it was presumably shelved.

[9][18] Paxton hosted The Secret Life of Water, the first episode of the series Planet H2O, which premiered in April 2006 on public television stations.

Paxton starred in the CW drama series The Beautiful Life alongside Corbin Bleu, Mischa Barton and Elle Macpherson.

[25] In 2018, she co-starred as Donna Rice opposite Hugh Jackman in Jason Reitman's The Front Runner, a biographical film about politician Gary Hart.

[citation needed] Paxton has a supporting role in Andrew Dominik’s Blonde (2022), based on the biographical fiction novel of the same name by Joyce Carol Oates.