Here is the full list of all 36 Tony Hawk's Pro Skater 1 + 2 achievements.
Unlock School in THPS1 Classic.
Reach Career level 100.
Complete all Gap collections.
Complete all "Hard" Get-Theres.
Give 50 Letters in Horse.
Earn the "Legend" Challenge Collection.
Earn 5,000,000 points in Trick Attack across all playtime.
Earn a score of 10,000,000 in any park in a 2 minute session or single combo. Game Mods must be disabled.
Paint 100 surfaces in Graffiti across all playtime.
Find every alien plushie.
Earn the "Veteran" Challenge Collection.
Place 500 objects in CAP.
Earn 2,000,000 points in Combo Mambo across all playtime.
Complete a match in multiplayer.
Spend $10,000 in the Skate Shop.
Land a 1,000,000+ point combo.
Achieve a High Score of 1,000,000+ on any classic Park.
Unlock Officer Dick.
Create a new park and upload it.
Get hit by a vehicle on every map that features them.
Earn the "Rookie " Challenge Collection.
Create a skater using the CAS system.
Find all Stat points for any Pro Skater.
Achieve a judge score of 99.9 on a competition run.
Get hit by the Bull in Bullring.
Complete every goal in THPS2 Classic and gain all gold medals.
Unlock Bullring in THPS2 Classic.
Earn any 4 Medals on competition parks in Tours.
Unlock School II in THPS2 Classic.
Complete every goal in THPS1 Classic and gain all gold medals.
Unlock Roswell in THPS1 Classic.
Bail a 100,000+ point combo.
Earn a Medal on any competition park in Tours.
Reach Career level 10.
Break 20 Panes of Glass.
Land a 50,000+ point combo.