Here is the full list of all 40 Goosebumps: The Game achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Be proactive and start your laundry.
Defeat Slappy while wearing the Haunted Mask.
Gather all possible items dropped from the laundry chute.
Recreate a crime scene to get security off your scent.
Correctly answer a riddle as if your life depended on it.
Achieve a perfect game of skeeball.
Survive a power outage with gnome complications.
Survive the game to completion.
Discover Slappy's secret shame.
Find entry into the bookstore.
Find a way to call RL Stine without touching gross coins or a dirty phone receiver.
Charge your cell phone.
Find a way inside the Mall.
Convince your brother to give you a ride across town.
Intimidate a very deadly creature.
Narrowly escape defeat by wearing a talisman into the woods.
Look into an antique mirror and do some self reflection.
Solve a compression problem to reach the attic.
Access the mysterious dimension from every possible angle.
See to the needs of the 3 unexpected guests.
Use modern technology to give the second Ghost Child his heart's desire.
Take a photograph using the Haunted Camera.
Disable a deadly toy bent on destruction.
Evict an elderly intruder.
Tell Aunt Dahlia about your weekend plans.
Face what lies beneath the sink... and survive!
Toss 10 expendable items into a deep, dark hole.
Complete Area 1 and return home.
Place the Magician's Top Hat on its rightful owner.
Find a way past the strange man in the woods.
Collect the cell phone from your school locker.
Track down RL Stine in the phone book and give him a call.
Have your life ended in 10 unique ways.
Take pictures of every monster possible using the Haunted Camera.
Complete the game without ever using the cell phone.
Complete the game after draining your phone to 0% battery.
Pry the Haunted Mask off your face.
Finish the game in # turns or fewer.
Grab every item you possibly can.