Here is the full list of all 33 The American Dream achievements.
Shoot all 48 hidden stars
Experienced the true ending
(Chapter 20) Complete the stage without a single civilian casualty
(Chapter 13) Listen to all of Rex's objection before shooting him
Experienced the fake ending
(Chapter 22) Witness the dawn of the Second American Revolution
(Chapter 21) Blow up 20 cars
(Chapter 15) Shoot 15 beer cans into the trash can
(Chapter 19) Shoot a fish in mid-air
(Chapter 17) Eat the entire stack of waffles
(Chapter 18) Keep checking records even after given the option to Give Up
(Chapter 16) Ensure all daisies survive til the end of the stage
Buy 50 Guns
(Chapter 14) Complete the stage without letting a single rat dough through
Shoot half the hidden stars
Manually eject and reload your gun 100 times
(Chapter 12) Hit yourself in the head with toilet paper
Eat 30 pieces of food
(Chapter 9) Defeat the hose without getting hit by any bolts
(Chapter 6) Shoot down 5 pins from the back row in the shooting game
(Chapter 5) Change your mind about which one of the twins you like
(Chapter 4) Catch the fast ball with your face
(Chapter 3) Shoot the down the ducks with 100% accuracy
Reach Intermission
Pump the shotgun 10 times without shooting
(Chapter 11) Learn how babies are made
(Chapter 10) Eat all of the maggots from the cheese
Shoot 1000 bullets
(Chapter 8) Out-dance Rex George
(Chapter 7) Earn at least $5.00
Make a milkshake
Shoot 1 hidden star
(Chapter 1) Begin your journey into The American Dream