skip graphical navigation
PBS KidsZOOM Home Back to Activity
Science Rocks!

Secret Candy Safe


your results

Sent in by:
Kenneth of Phoenix, AZ

An alarming way to keep your secrets safe!

Materials Needed

  • cardboard boxes with lids
  • copper wire
  • batteries
  • buzzers
  • string
  • aluminum foil
  • paper clips
  • mini slinkys
  • markers
  • masking tape
  • electrical tape
  • scissors
  • your secret stash of Halloween candy



  1. To keep your family members from munching on your secret stash of Halloween candy, build a safe with an alarm.
  2. Use a cardboard box, a battery, a buzzer and any of the above materials to make your safe.
  3. Think about what problem you are trying to solve. How will you get the buzzer to go on when someone opens the box? For the buzzer to sound, it has to be connected to the battery by wires. How can you make two wires touch when the box is open that don't touch when it's closed? How will you keep the alarm from going off if you want to get into your safe? Check out the ZOOMsci Door Alarm for more ideas on how build a circuit with a switch.
  4. Test your design. If it doesn't work make changes to your design and try again.

Trace the flow of electricity through your alarm circuit. Did you build a complete circuit into your design? In a complete circuit, the electricity from the battery flows along one wire to the buzzer, along the other wire and then back to the battery. The moving electricity makes the buzzer sound. If you disconnect one wire, the electricity stops moving because you broke the circuit. How does your switch interrupt the flow of energy to stop the alarm?
What if you had something you wanted to protect that couldn't fit in your safe? What would you need to put an alarm on a drawer or a closet? Test it out and be sure to send your designs to ZOOM.

Some of your Results

Micheal of Yankton, SD wrote:
it was cool my brother got caught.

ZOOM Fan, age 10 of Olathe, KS wrote:
I used it to keep my Diary safe, it worked the first time and scared my 6 year old sister so much she ran out of the room before I could get on her! Thanks for the idea!

Davy, age 7 of Dallas wrote:
i lost it, but it was cool! I did not use the buzzer! I used a shoe box, paper, croyns, and siccers.

Regina, age 12 wrote:
I kept on eating the candy, and thinking of a combination for it.

Christina, age 16 of Hartford, CT wrote:
No longer will my candy be stolen from me! This is the coolest thing in the universe! Why put money in a safe when you can hide your candy in it! Time to chow down on my hidden candy! LIVE ON CANDY LOVERS!!

Billy, age 8 of Portchester, NY wrote:
I and my sister had our own candy safes. we did not use anything but candy and a box. the other things I used are stick pads, crayons to write with, treats, and prizes.

Moshanique, age 12 of Virginia Beach wrote:
my brother and I used duck tape, dickurays, other things. I love everthing that you do and you are my numer 1.

Sydney, age 10 of Muskogee, OK wrote:
It was so funny im 10 my brother is 15 & he tried to get 9in it and he got caught and I highly doubt hell do it again.(unless he really wants my candy)

Kenichi, age 12 of Tokyo, Japan wrote:
This design worked! it was so good I left my secret candy safe unhidden and exposed.

Jacob, age 9 of Fremont, CA wrote:
I used a shoebox and a snap circuits set to make the secret candy safe. It sets off an alarm and works fabulous!

Kiari, age 6 of Kansas City, KS wrote:
It was socool when the combination was opened!! It took me and my mom about a hour an a half but it really worked. I used tape, books and something to block the other numbers.

Saadat, age 6 of Bangladesh wrote:
My 12 year old sister ran out the door when she heard the buzzer.

Kenia, age 11 of Randolph, MA wrote:
I was so happy I tried this out because my family always eats my delicious candy at first the wires crossed but on the second time it worked.

Bailey, age 9 of Cedar Rapids, IA wrote:
When my 1 year old brother opened it the buzzer whent off and it scared my baby brother so much. I also did it to my 13 year old sister but it did not scare her.

Sarah, age 8 of Phoenix, AZ wrote:
It started buzing, the slinkes bounced up and I put a record mickrufon on it and it said "get out of the candy, step away"!

Jacob, age 8 of Raleigh, NC wrote:
When we opended the box lid with the weight, the lid hit a on off button causing the alarm to go off.

Meghan, age 11 of Alachua, FL wrote:
It happened awsome just the way I wanted it because my mom said I'm gonna take all your candy away from you and I'm gonna find your candy and so she went into my room and saw this box that said candy and when she saw it she said I found the candy but when she opened it up the alarm went of it was so cool.

Meagan, age 12 of Little Falls, MN wrote:
Every year my sisters take my candy! This was an awsome way to keep my sisters away from it.

Joshua, age 13 of Jersey City, NJ wrote:
I had so much fun making it. It scared my older brother so much I wanted to scare my whole family with it.

Emily, age 10 of Grand Island wrote:
When my brother opend the safe the alerm went off.

Jeremy, age 12 of Greenwood, MO wrote:
It worked great! I had a fun time making it and it scared my brother half to death when he tried to get candy!

not yet implemented