Spooky LED Necklaces

As part of our "Spooky Science Saturday" where elementary kiddos come to the high school for science stations and demonstrations, we have introduced a take-home science craft. In this blog post, I wanted to share the materials for this light up necklace in case anyone else wants to make one of their own for a STEM craft that can be used for trick-or-treating.

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Materials

One of the things that makes this craft perfect for a make and take is that the materials come to a little over a $0.25 a piece which is pretty good for a light up necklace that works!

The following are some links to the required materials that we purchase each year

Flashing LEDs

I'm amazed that these RGB flashing LEDs are as cheap as they are! It makes for fun spooky eyes

Solid LEDs

These solid color LEDs are a nice set for really cheap

Button Batteries

My price point on batteries is under $0.25 if I can. The packaging is intentionally tricky and requires scissors for most listings but this one is a little easier access

String

Any string will do but this set has a lot of great colors

Double-Sided Tape

For attaching the battery/bulbs to the design. Glue would also work but double-sided tape is fast and mess-free :)

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3D Printed Battery/Bulb Holder

A big reason that this craft is possible and safe (button batteries are generally not a good idea around kids for swallowing dangers) is the 3D printed battery/bulb holder.

3D Files on Makerworld

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Cutout Pumpkins and Ghosts

The character could really be anything as long as there are eyes space a little over 0.5" apart. I have a couple of options that could be printed and cut or cut out using a Cricut Machine.

Ghosts and Pumpkins (pdf)
File Size:	76 kb
File Type:	pdf

Download File

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Ghosts and Pumpkins (editable)
File Size:	1453 kb
File Type:	pptx

Download File

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Cricut Files:

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Pumpkin Cutouts

Ghost Cutouts

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Assembly

Step 1: Snap in the Battery
The 3-Volt 2032 button battery securely snaps into place and built in grooves guide the LED leads into place and hold them snug against the battery.
To remove the battery, just use the edge of a table to push on the battery through the semicircular cutout on the holder.

Step 2: Insert LEDs
There are slots on the side of the battery holder that will hold the LED leads securely against the surface of the battery. When assembling, remember that LEDs only work one direction and the long wire must be connected to the positive side (shiny side) of the battery.

Step 3: Connect the Lanyard Holder
Gently pull out on the tabs to allow the battery holder to snap into the lanyard holder.

Step 4: Thread the String
Cut a string to the appropriate length and thread through the hole on the lanyard holder piec

Step 5: Add Design with Cutout Eyes
The LEDs are spaced out so that the battery holder can be taped to the back of a piece of card stock and designed as eyes for a ghost or other character from the files above

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Happy Halloween!!