Here is the full list of all 38 Danganronpa S: Ultimate Summer Camp achievements.
Develop 50 characters or more and clear Monotaro's Hope
Develop 40 characters or more and clear Monophanie's Hope
View all of a character's events
Craft all equipment in Battle Mode
Clear Floor 200 in Battle Mode
Craft all Ultimate Proofs
Craft all weapons in Battle Mode
Obtain all Character Cards
Clear Floor 150 in Battle Mode
Obtain all Presents
Develop 30 characters or more and clear Monodam's Hope
Defeat secret boss for the first time
Clear Floor 100 in Battle Mode
Spin the Golden MonoMono Machine 10 times
Obtain password for the first time
Develop 20 characters or more and clear Monosuke's Hope
Equip all party members in Battle Mode
Defeat Monobeast (Human) in Development Mode for the first time
Obtain all Ultra Despair Girls Character Cards
Obtain all Danganronpa Character Cards
Obtain all Danganronpa V3 Character Cards
Obtain all Danganronpa 2 Character Cards
Develop 10 characters or more and clear Monokid's Hope
Unlock the fifth island for the first time
Craft 1 equipment in Battle Mode
Clear Floor 10 in Battle Mode
Spin the MonoMono Machine 10 times
Unlock the fourth island for the first time
Spin the MonoMono Yachine 10 times
Develop 1 character
Unlock the third island for the first time
Unlock the second island for the first time
Clear Welcome to Jabberwock Island
Unlock all achievements
Clear Graduation
Clear Re:Welcome to Jabberwock Island
Clear the epilogue
View all of every character's events