The Christmas Spirit-Will Eisner-1950-The 12 Days 'Til Christmas # 10

Suzanne-1957-The 12 Days 'Til Christmas # 11

America's First Christmas Tree-1947-The 12 Days 'Til Christmas # 12

Bob Brant and the Trouble Shooters-Carl Hubbell-1953

Not to be outdone, Lev Gleason had BOY Comics so Timely had MAN Comics. Lev Gleason had the Little Wise Guys so Timely offered up the Trouble-Shooters.

Rover-Can He Talk?-1959

Not so good dog art this time. GCD says it's Tony Tallarico (replacing an earlier listing of Bill Fracio, Tony's longtime collaborator) but I believe I have to disagree with my learned friend, Nick Caputo. I see only a single panel that makes me think of Tallarico. 

Snagglepuss/Huckleberry Hound-Mark Evanier/Scott Shaw!-1979

This Hanna-Barbera outing is actually one long in-joke, as Mark Evanier explains here. 

Big Boy-Dan DeCarlo-1957

Here we see the East Coast Big Boy from the period where the Big Boy comics were still being produced by the company that would eventually become Marvel.