When Carson Taylor is present in the NCIS office, he is playing a video game. When you see the graphics of that particular game, you see clearly that the images are scenes of attacking Cylon Raiders from Battlestar Galactica (1978). Donald P. Bellisario was also involved as writer and producer of that series.
When Tony and Ziva are in Carson's bedroom, Tony gushes over the bed modeled on the Ferrari driven by Tom Selleck in Magnum, P.I. (1980). NCIS (2003) series creator Donald P. Bellisario also created Magnum, P.I. (1980).
Between Special Agent Timothy McGee and Youth Ranger Carson, their Ranger uniforms contain at least four official Boy Scouts of America merit badges. Citizenship in the Community: a church and a forest; Wood Carving: a blue background with a totem pole; Emergency Preparedness: a gray background with a blue house, gold cross and green lightning with green Morse code; Citizenship in the World: a blue globe with yellow, blue, red and green continents.
Both McGee and Carson wear a merit badge that appears to be a modified version of the BSA First Aid badge, which traditionally features a gold cross on a red field. The modified badge has a gold cross on a silver background instead. Although the color is incorrect, it's appropriate that both characters wear some version of the First Aid badge since it must be earned prior to earning the Emergency Preparedness badge that both of them also wear. (This is alluded to by the small gold cross featured on the Emergency Preparedness badge.)