Full list of all 68 Skate 3 achievements worth 1,500 gamerscore. It takes around 25-30 hours to unlock all of the achievements in the base game on Xbox 360.
The base game contains 47 achievements worth 1,000 Gamerscore, and there are 3 DLC packs containing 21 achievements worth 500 Gamerscore.
Kill 80 challenges
Win any 5 Ranked Challenges
Upload 5 Films and 5 Photos, and 3 skate.Parks
Own all of the lots
Everything beaten, everything unlocked, everything earned
Own all challenges
Complete all pro challenges
Complete all Promotional Films and Photos
Own all of the spots
Get the covers of Skateboard Mag and Thrasher
Win the street and tranny ender contests
Win a Ranked Online Solo Challenge
Beat the film ender
Win a Ranked Team Own The Lot
Win a Ranked Online Team Challenge
Rate 5 skate.Parks, 5 Films, and 5 Photos
Win the Monster contest
1 Million boards sold
Create a Logo and put it on your Skater
Complete an Online Career challenge
30,000 point line
Win the T-Mobile sponsored contest
Win the Goofy vs. Regular contest
Play in a 6-player Team Freeskate session
Be part of a team with two or more skaters
10,000 point trick
Fully staffed your team
Win the final deathrace
3 Moveable objects used in a single sequence
Catch the Skate Flu
Perform a 100 meter or 300 foot grind
Beat the "Thorax Crunch" Hall of Meat Challenge
Fly Spread Eagle for 10 seconds
Earn your third career teammate
Win both Maloof Money Cup contests
Get the terrain meter in the red for your own skate.Park
Complete the skate.Park tutorials
Land a Miracle Whip (Superdude body flip)
Earn your second career teammate
3 manuals in a single sequence
Complete Coach Frank's skate.School Tutorials
Call a Skater to come skate with you
Unlock the Team HQ
75,000 point bail
Earn your first career teammate
Start your team
Reach community board sales target
Complete the Maloof NY Tranny OTL
Complete the Maloof NY Street OTL
Complete both Maloof NY OTS Challenges
Complete both Maloof NY Photo Challenges
Win the Maloof NY Contest
Beat Danny Way in the Final Contest
Complete the Danny Way Street Path
Complete the Danny Way Tranny Path
Complete both Danny Way OTS Challenges
Complete the "Jungle Step" and "Danny's Mega Gaps" Challenges
Complete the "Touch and Go" and "Gazebo Film" Challenges
Complete both Demos
Complete the "Marraffa's Skatepark" OTL Challenge
Complete the "Gallery Gap Line" Film Challenge
Complete "The Quintessential Stair" Film Challenge
Complete the "Bump Riser" OTS Challenge
Complete the "Twin Spires" OTS Challenge
Complete the "Modern Manual" Photo Challenge
Complete "The Art of Rail" Film Challenge
Complete "The Corkscrew" Photo Challenge
Complete the "Over the Rainbow" Photo Challenge