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.
Complete the game without ever using the cell phone.
Track down RL Stine in the phone book and give him a call.
Grab every item you possibly can.
Take pictures of every monster possible using the Haunted Camera.
Finish the game in # turns or fewer.
Tell Aunt Dahlia about your weekend plans.
Defeat Slappy while wearing the Haunted Mask.
Discover Slappy's secret shame.
Gather all possible items dropped from the laundry chute.
Have your life ended in 10 unique ways.
Toss 10 expendable items into a deep, dark hole.
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.
Pry the Haunted Mask off your face.
Be proactive and start your laundry.
Survive the game to completion.
Complete the game after draining your phone to 0% battery.
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.
Disable a deadly toy bent on destruction.
Take a photograph using the Haunted Camera.
Find a way inside the Mall.
Intimidate a very deadly creature.
Access the mysterious dimension from every possible angle.
Convince your brother to give you a ride across town.
Look into an antique mirror and do some self reflection.
Solve a compression problem to reach the attic.
Use modern technology to give the second Ghost Child his heart's desire.
See to the needs of the 3 unexpected guests.
Evict an elderly intruder.
Face what lies beneath the sink... and survive!
Narrowly escape defeat by wearing a talisman into the woods.
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.