As of November 2008, Arnold was attending Ryerson University, majoring in broadcast journalism.

Then after a few minor roles, she had a role in the movie Custody of the Heart for which she was nominated for the 2001 Young Artist Award for Best Performance in a TV Movie (Comedy or Drama) for a Young Actress Age Ten or Under.

Over the next few years, she had roles in a few more made-for-TV movies, such as Harlan County War, One Kill, Range of Motion, and Jewel.

Beginning in 2005 , she starred for three seasons as the title character of the popular Family channel series Naturally, Sadie until 2007.

In 2010, she won a Gemini Award for Best Performance in a Children's or Youth Program or Series, in a season 9 episode of Degrassi.