Posted this elsewhere, thought it might generate some interesting discussion here.
Let's face it, child actors are rarely believable in their roles, because they just don't have the maturity to tackle the job of accurately taking over the persona of being someone else. That said, in the history of film there have been those rare stand out moments where a child actor just absolutely nails a role and you completely forget that they're acting. In many of those cases, those child actors have gone on to become great adult performers as well. This isn't a scientific poll or anything, but solely based on my opinion, I bring you my list of the Top 25 All Time Performances by Child Actors.
25. Corey Haim in Lucas
24. Jaden Smith in The Pursuit of Happyness
23. Anna Chlumsky in My Girl
22. Chloe Moretz in Kick Ass
21. Tatum O'Neal in The Bad News Bears
20. Dakota Fanning in I Am Sam
19. Elijah Wood in Radio Flyer
18. Ricky Schroeder in The Champ
17. Corey Feldman in Stand By Me
16. Drew Barrymore in E.T.
15. Wil Wheaton in Stand By Me
14. Elijah Wood in The War
13. Jodie Foster in Taxi Driver
12. Leonardo DiCaprio in What's Eating Gilbert Grape
11. Linda Blair in The Exorcist
10. Elijah Wood in The Ice Storm
09. Christian Bale in Empire of the Sun
08. Abigail Breslin in Little Miss Sunshine
07. Henry Thomas in E.T.
06. River Phoenix in Stand By Me
05. Haley Joel Osment in The Sixth Sense
04. Hailee Steinfield in True Grit
03. Anna Paquin in The Piano
02. Kirsten Dunst in Interview with The Vampire
01. Natalie Portman in The Professional