1. "Thirteen month-old baby broke the looking glass" (1972): "Superstition," Stevie Wonder
2. "I am only five years old and my baby's three" (1959): "Baby Talk," Jan and Dean
3. "We were together since we were five" (1975): "Emma," Hot Chocolate
4. "When you were only six, I was your big brother" (1961): "Happy Birthday Sweet Sixteen," Neil Sedaka
5. "Mama taught me how to pray before I reached the age of seven" (1971): "Put Your Hand in the Hand," Ocean
6. "And at the age of thirteen I thought I was carrying the weight of the whole world on my shoulders" (1970): "Patches," Clarence Carter
7. "She's just sixteen years old, leave her alone, they say" (1980): "Into the Night," Benny Mardones
8. "Well, she was just seventeen, you know what I mean" (1964): Oh, come on, you know this
9. "You've been telling me you were a genius since you were seventeen" (1973): "Reelin' in the Years," Steely Dan
10. "At seventeen we fell in love, high school sweethearts" (1980): "Too Hot," Kool and the Gang
11. "Twenty-four and there's so much more" (1972): "Old Man," Neil Young
12. "Speed jive don't want to stay alive when you're twenty-five" (1972): "All The Young Dudes," Mott the Hoople
13. "I'm not the cat I used to be, I got a kid, I'm thirty-three baby" (1984): "Middle of the Road," Pretenders
14. "Seventeen has turned thirty-five, I'm surprised that we're still living" (1987): "Cherry Bomb," John Mellencamp
15."She's forty-one and her daddy still calls her baby" (1973): "Delta Dawn," Helen Reddy
16. "Seventeen years old, he's touching sixty-four" (1978): "Hot Legs," Rod Stewart
17. "At sixty-five years old, my mother, God rest her soul" (1972): "Alone Again (Naturally)," Gilbert O'Sullivan

Bonus: According to Paul Hardcastle, "In World War II the average age of the combat soldier was 26. In Vietnam it was" how old?: 19