PAW Patrol (lost pitch pilots and early concepts of Nick Jr. animated series; 2008-2013)
PAW Patrol is a Nick Jr. computer-animated series created by Keith Chapman. The series revolves around a boy named Ryder with a crew of rescue dogs and pups that work on missions in the fictional Adventure Bay.
The show has gone through a vast amount of changes before its initial premiere in 2013. There are believed to be a variety of pitch pilots and concept tests from before the series was finalized, and these have not seen the light of day. Sometime in 2008, the first piece of concept art was created titled Raffi and the Rescue Dogs, the first piece of concept art was created by Keith Chapman who also worked on other shows at the time.
Robbie’s Rescue Dogs
Status: Existence Unconfirmed
In an unknown timestamp, concepts and a possible pitch pilot were proposed by Spin Master and developed by Keith Chapman. The working title at this time was Robbie's Rescue Dogs, Ryder was also named Robbie in this stage.
Currently, nothing of this stage outside of concept art resurfaced.
Robbie's Pup Pack
In 2010, another concept was pitched, approaching for a realistic design and the name Robbie's Pup Pack (also known as Robbie's Rescue Pups). A variety of design changes were pitched and considered during this phase.
There is a lack of information about this phase in development, however an image of the earlier concept art was given to the NickALive! blog by Keith Chapman. A few pieces of concept art were also available on John Mariella's website, but have since been taken down and only a few have been archived.
There is confirmed to exist an animation test and a trailer that was pitched and shown to Nick Jr. during either this phase or an earlier one, but this has never resurfaced as of now. According to John Mariella's website, there was an Otter character in the test scene. 
Ryder's P.A.W. Patrol
Status: Existence Unconfirmed
Around 2012, another concept was pitched, this time having the name Ryder's P.A.W. Patrol. (The acronym for PAW is “pups at work”) The design was changed drastically and resembled the final show more in terms of these factors, outside of the fact that designs were still 2D in this stage. The name Ryder was also finalized during this stage.
One scrapped character during the development was a dog named Timber, who resembled the design and would've been the companion of another character named Jake. The reason why Timber was scrapped is unknown, however he was replaced with Everest in the final series. The change from 2D to 3D for designs happened sometime in late 2012 or 2013.
There exists multiple pieces of concept art from this stage, however it is not known if any animation or tests exists, though it is most likely they exist in some format.
While concept art exists and has resurfaced for most of the stages, any animation tests, trailers, or footage has currently not seen the light of day yet. Only one stage is also confirmed to have footage as of now.
It is unknown if any more concept art or images will be posted by production members or make its way online.
Robbie’s Pup Pack
Ryder's PAW Patrol
Bumpers and Interstitials
- Loretta the Letter Lady (partially found Nick Jr. short interstitial series; mid 1990s)
- Nick Jr. (partially found revamped Face promos of Nickelodeon channel block; 2003-2004)
- Nick Jr. Power Play Summer (partially found Nick Jr. interstitial series; 2005)
- Snappy Larry's Showtime (partially found Nick Jr. UK interstitial series and American dub; mid-2000s)
- The Backyardigans (partially found Nick Digital pilot of Nick Jr. CGI animated series; 2002)
- Blaze and the Monster Machines (lost pitch pilot of Nick Jr. animated series; existence unconfirmed; 2012)
- Blue Prints (found unaired pilot of "Blue's Clues" Nick Jr. animated/live-action series; 1994-1995)
- Bubble Guppies (found pitch pilot of Nick Jr. CGI animated series; 2006)
- Dora the Explorer (partially found unaired pilots of Nick Jr. animated series; late 1990s)
- Me and My Friends (partially found live-action pilot of "The Backyardigans" Nick Jr. CGI-animated series; 1998)
- Oswald (lost pitch pilot of Nick Jr. animated series; late 1990s)
- Peppa Pig (found pitch pilot of Channel 5 animated series; 2002)
- Super Why! (found stop-motion Nick Jr. pilot of PBS Kids CGI animated series; 1999)
- The Umizumiz (partially found pitch pilot of "Team Umizoomi" Nick Jr. live-action/CGI animated series; 2008)
- Wallykazam! "Monty's Magic Words" (partially found pilot for Nick Jr. education series; 2010s)
- Wow! Wow! Wubbzy! (partially found unaired original pilot of children's animated TV series; 2005)
- Yo Gabba Gabba! (found pilots/test demo of live-action/puppet musical TV series; early 2000s/2006)
- As Pistas da Blue (partially lost Portuguese adaptation of "Blue's Clues" Nick Jr. animated/live-action series; mid-2000s)
- The Backyardigans (partially lost British dub of Nick Jr. CGI-animated series; mid-late 2000s)
- Binyah Binyah! (found spin-off of "Gullah Gullah Island" Nick Jr. musical series; 1997-1998)
- Blue's Clues (found British adaptation of Nick Jr. animated/live-action series; 1998-2003)
- Bubble and Squeak (partially found Nick Jr. UK live-action puppet series; 2007-2010)
- Downward Doghouse (partially lost precursor to "Ni Hao, Kai-Lan" Nick Jr. animated series; 2000s)
- Made by Maddie (partially found Nick Jr. animated series; 2020)
- Peppa Pig (partially found American dub of Channel 5 animated series; 2005-2007)
- Riddle Blue/수수께끼 블루 (partially found Korean adaptation of "Blue's Clues" Nick Jr. animated/live-action series; 2000-2001)
- Whoopi's Littleburg (partially found Nick Jr. musical miniseries; 2004)
- Wow! Wow! Wubbzy! (partially found British dub of children's animated TV series; late 2000s-early 2010s)
- NickALive article where Keith Chapman shared concept art, and talked about the development with Jen Dodge, whom confirmed the existence of an animation test and a trailer. Retrieved 16 Oct '23
- Trademark filing for Ryder's PAW Patrol dated March 2012. Retrieved 16 Oct '23
- Amanda Zima's Tumblr with concept art for Everest. Retrieved 16 Oct '23