Nickelodeon is growing its unscripted slate with new competition series Top Elf.

Beginning production in September and premiering in December, the five x 60-minute show will feature seven kids going through building and design skills competing in holiday-themed challenges to be named “top elf” and win everything on the wish list of someone in their community.

The series is created by Ugly Brother Studios’ Mike and Tim Duffy (Eat the World with Emeril Lagasse), who serve as executive producers alongside Jimmy Fox through Los Angeles-based prodco Main Event Media. Bob Schermerhorn (Project Runway All Stars, America’s Next Top Model), Lisa Fletcher (The Titan Games) and Nickelodeon’s VPs of unscripted content Paul J Medford and Mandel Ilagan are all EPs, with Fletcher also working as showrunner. Michael Pearlman (Chopped, Project Runway All Stars) is directing.

Doubling down on unscripted, Nickelodeon also ordered a full 10 x half-hour season of its hidden camera prank show The Substitute (pictured) in addition to the previous two eps it ordered earlier this year. The series features celebs who are transformed by a team of special effects artists to go undercover as substitute teachers in schools, camps and other locations.

The first two episodes starring Jace Norman (Henry Danger) and comedian Lily Singh were well-received with kids six to 11, averaging almost 700,000 total viewers, which led to the pick up, according to a Nickelodeon spokesperson. Produced by California-based prodco The Intellectual Property Corporation, Eli Holzman, Aaron Saidman and Todd Hurvitz (Punk’d) serve as EPs, with Hurvitz also serving as the showrunner. Jessica Brown, Nick’s executive in charge of production and VP of current series, also serves as an executive producer.

On top of these two new shows, Nickelodeon also greenlit a number of unscripted series back in February, including America’s Most Musical Family and Are you Smarter Than a 5th Grader as part of a bigger move into the unscripted space. The kidcaster also bolstered its efforts by appointing unscripted TV vet Rob Bagshaw as its EVP of unscripted content, earlier this year.