Here is the full list of all 23 Long and Hard... Summer! achievements.
Build a stronger bond (heart level 3) with Yui Harada.
Build a stronger bond (heart level 3) with Kaname Mao.
Build a stronger bond (heart level 2) with Yui Harada.
Build a stronger bond (heart level 3) with Akari Tanaka.
Build a stronger bond (heart level 1) with Yui Harada.
Build a stronger bond (heart level 2) with Kaname Mao.
Build a stronger bond (heart level 2) with Akari Tanaka.
Get at least a 'D' grade till Friday, week 8.
Build a stronger bond (heart level 1) with Akari Tanaka.
Complete the quest 'Party Time!'.
Complete the quest 'The Old Babbler'.
Build a stronger bond (heart level 1) with Kaname Mao.
Complete the quest 'Not a Nuisance'.
Complete the quest 'Sweet Secret'.
Complete the quest 'The Real Culprit'.
Complete the quest 'Spooky Refrigerator'.
Complete the quest 'Bills, Bills Everywhere'.
Complete the quest 'Bare Rivals' and beat Kaname's record in the arcade game.
Get a score of 10 000 or more in the arcade game.
Complete the quest 'School's Computer'.
Complete the quest 'Leaking Pipe'.
Complete the quest 'Someone to Hug'.
Complete all the levels in the game that you can play on your PC at home.