Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Pit Boss (30 points): Show that pit who's boss.
Preservation of Mass (20 points): Break the rules in Test Chamber 07.
Pturretdactyl (5 points): Use an Aerial Faith Plate to launch a turret.
Lunacy (20 points): That just happened.
Drop Box (20 points): Place a cube on a button without touching the cube.
Overclocker (30 points): Complete Test Chamber 10 in 70 seconds.
No Hard Feelings (10 points): Save a turret from redemption.
Schrodinger's Catch (20 points): Catch a blue-painted box before it touches the ground.
Ship Overboard (10 points): Discover the missing experiment.
Final Transmission (20 points): Find the hidden signal in one of the Rat Man's dens.
Good Listener (5 points): Take GLaDOS' escape advice.
Scanned Alone (5 points): Stand in a defective turret detector.
The Part Where He Kills You (20 points): This is that part.
Bridge Over Troubling Water (10 points): Complete the first Hard Light Bridge test.
SaBOTour (10 points): Make a break for it.
Stalemate Associate (15 points): Press the button!.
Wake Up Call (5 points): Survive the manual override.
You Monster (5 points): Reunite with GLaDOS.
Undiscouraged (10 points): Complete the first Thermal Discouragement Beam test.
White Out (15 points): Complete the first Conversion Gel test.
Tunnel of Funnel (15 points): Master the Excursion Funnel.
Dual Pit Experiment (15 points): Do the same test twice.
Tater Tote (15 points): Carry science forward.
Vertically Unchallenged (15 points): Master the Repulsion Gel.
Stranger Than Friction (15 points): Master the Propulsion Gel.
Professor Portal (75 points): After completing co-op, complete Calibration Course online with a friend who hasn’t played before.
Air Show (20 points): Perform 2 aerial gestures before touching the ground in co-op.
Portal Conservation Society (20 points): Complete Chamber 3 in the Hard-Light Surfaces co-op course using only 5 total portal placements.
Empty Gesture (25 points): Drop your co-op partner in goo while they are gesturing by removing the bridge under them.
Party of Three (25 points): Find the hidden companion cube in co-op test chamber.
Narbacular Drop (25 points): Place a portal under your co-op partner while they are gesturing.
Asking for Trouble (10 points): Taunt GLaDOS in front of a camera in each of the five co-op courses.
Rock Portal Scissors (20 points): Win 3 co-op games of rock-paper-scissors in a row.
Friends List With Benefits (50 points): While playing co-op, hug 3 different people on your friends list.
Four Ring Circus (25 points): Enter 4 different portals without touching the ground in co-op.
Triple Crown (15 points): Solve 3 co-op chambers in the Mass and Velocity course in under 60 seconds each.
Still Alive (15 points): Complete Course 4 with neither you nor your co-op partner dying.
Can't Touch This (10 points): Dance in front of a turret blocked by a hard light bridge in co-op.
Smash TV (75 points): Break 11 test chamber monitors.
High Five (5 points): Celebrate your cooperative calibration success.
Team Building (10 points): Complete all test chambers in the Team Building co-op course.
Door Prize (20 points): Examine all the vitrified test chamber doors.
Portrait of a Lady (10 points): Find a hidden portrait.
You Made Your Point (10 points): Refuse to solve the first test in Chapter 8.
You Saved Science (100 points): Complete all test chambers in all courses of co-op.
Iron Grip (20 points): Never lose a cube in Chamber 6 of the Mass and Velocity co-op course.
Gesticul-8 (15 points): Perform all 8 gestures of your own volition in co-op.
Confidence Building (10 points): Complete all test chambers in the Mass and Velocity co-op course.
Bridge Building (15 points): Complete all test chambers in the Hard-Light Surfaces co-op course.
Obstacle Building (15 points): Complete all test chambers in the Excursion Funnels co-op course.