The LEGO 4 Juniors theme was a short-lived product line available from 2003 to 2004, designed as a simplified bridge between the larger DUPLO bricks and the standard, more complex LEGO System bricks.
Theme Overview
The 4 Juniors theme aimed to provide a building experience suitable for children around the age of four (hence the name "4 Juniors"), offering larger, pre-built or simple-to-assemble parts. The sets often used bigger pieces that were easier for little hands to handle, with some pieces that were incompatible with the main LEGO System bricks.
Sub-themes and Sets
The line was divided into several sub-themes based on popular licensed properties and general themes.
SpongeBob SquarePants (2004): This was the first iteration of the LEGO SpongeBob theme.
Bikini Bottom Express (Set number: 10108)
Mr. Krabs Crab Shack (Set number: 10109)
Dinosaur (2004): Based loosely on the Dino Attack concept, these sets were simpler and more focused on capturing dinosaurs with basic vehicles.
Dino Explorer (Set number: 7000) Dino Observation Post (Set number: 7002)
Knights' Kingdom (2004): A simpler, non-story-based castle theme that preceded the more complex Knights' Kingdom II.
King's Castle (Set number: 4805)
Dragon Base (Set number: 4806)
Pirates (2004): A return to the classic Pirates theme with simplified designs.
Pirate's Ship (Set number: 7001)
Spider-Man 2 (2004): Tie-in sets for the Spider-Man 2 film.
Doc Ock's Crime Spree (Set number: 4858)
Doc Ock's Cafe Attack (Set number: 4854)
City (2003): General city and emergency service sets.
Fire Station (Set number: 6000)
Police Station (Set number: 6002)
Discontinuation and Successor
The theme was discontinued in 2004, and the concept of a "bridge" between DUPLO and standard LEGO was later revisited with the current LEGO Juniors theme (now part of the LEGO 4+ line within the main themes), which successfully uses standard LEGO pieces in simpler build instructions to help children transition.