Review: 40172 Brick Calendar | Brickset: LEGO set guide and database
Don't know how rare this is, but I found this serial number on a random brick in The End set : r/lego
Amazon.com: LEGO DUPLO Classic Brick Box Building Set with Storage 10913, Toy Car, Number Bricks and More, Learning Toys for Toddlers, Boys & Girls 18 Months Old : Toys & Games
LEGO Parts and Pieces: Red (Bright Red) 1x8 Brick x20
Amazon.com: LEGO Parts and Pieces: Red (Bright Red) 1x4 Brick x50 : Toys & Games
Hands-On Place Value Math Activity with LEGO Bricks - Frugal Fun For Boys and Girls
Understanding LEGO part numbers | Brickset: LEGO set guide and database