1) Composition change was the answer I had.
I really like the two additional answer DBM provided.
2) 1954 Elizabeth II strapless obverse
3) 2006 had 6 varieties: no logo, P,
RCM in mag and non mag
2003 had 5 varieties: no logo and P in with both diademed & uncrowned obverses, WP (uncrowned)
I like Chadcoins 1965 answer which is a close third.
4) 2006P - 233,000 minted
5) 1937 (new monarch)
1948 (independence of India)
1953 (new monarch)
1967 (centennial of Canada)
1992 (125 year anniversary, Canada)
2002 (50 years anniversary, Queen Elizabeth II reign)
6) copper, tin, zinc, nickel, steel
7) Alex Colville (1967), Fred Lewis (1920-1936)
8) Both come in blunt 5 and pointed 5 varieties.
9) Shape (round to 12 sided), weight (2.8 to 2.5 g)
10) Shape (12 sided to round), weight 2.5 g to 2.25 g, composition (copper to copper plated zinc)
11) All other pennies during the 2000's came in at least two variations: magnetic and magnetic
12) 1954 SS, 1965, 1979, 1990, 2003