Introduction: Float Away in This Slotted Construction Jellyfish Costume

This instructable is showing a school project at my high school to make a costume marine- themed for either a stage presentation or for Halloween. This costume is meant to fit the average middle school student (4-6 grade). The costume could only be constructed using slotted construction for easy flat pack storage.

Design Brief: 
Design and create a marine-themed animal or man-made object only out of recycleable material, preferably cardboard. Create only using slotted construction and for the use of the average middle school student.

-Made out of single, double, or tri-wall cardboard
-Marine theme
-Slotted Construction

-Only recycled materials
-No adhesives (Tape, Glue, etc.)
-Few parts/pieces

Step 1: Supplies

Cardboard 60" x 60" 

Step 2: Tools

(T1)  CUTTING MAT - For cutting cardboard on a safe surface
(T2) UTILITY KNIFE - For making cuts in cardboard
(T3) RULER - For measuring the cuts and folds
(T4) PENCIL - For making marks to make cuts
(T5) CIRCLE TEMPLATE OR COMPASS - For making perfect circles

Step 3: Parts

P1- Epidermis
P2- Tentacle

Step 4: Safety First

Put a cutting board (T1) down for safe cutting.

Step 5: The Layout

Lay a piece of cardboard (S1) flat on the ground.

Step 6: (P1) Epidermis: Circle

 Use a ruler (T3) and mark a diameter of 46" with a pencil (T4).

Step 7: Hole

Make another 7" diameter of a circle with a ruler (T3).

Step 8: Segments

With the ruler (T3) and pencil (T4) make eight equally spread out lines 2" away from the inner circle going straight out to the edge.

Step 9: Division

With the utility knife (T2) cut the straight lines leaving space away from the inner circle.

Step 10: Horizontal Flap

With the ruler (T3) and pencil (T4) make measurements from left to right 3" space from the left side and all the way through on the right, 2" above bottom to make an elongated flap.

Step 11: Slot

Measure 1.5" from left and make incision with same length as flap that was just made.

Step 12: Slot for Tentacle

 Make a 4" slit 2" above flap and in the direct middle of flap for tentacles with the utility knife (T2).

Step 13: Head Hole

Cut out inner circle for head opening with utility knife (T2).

Step 14: Helicopter Effect

Repeat steps 7 through 10, 7 more times for each segment.

Step 15: Repeat

Repeat all steps half scaled for a jellyfish dome hat.

Step 16: (P2) Tenticle

Make a rectangle with the perimeter of 4" by 12" with the ruler (T4) and pencil (T3).

Step 17: Wavy Lines

Make a wavy elongated shape staying in the dimensions of the rectangle and make sure both sides are parallel to make a tentacle shape.

Step 18: First Tentacle

Cut out with utility knife (T2).

Step 19: Repeat

Repeat steps 1-3, 7 more times for eight tentacles.

Step 20: Half Scale Hat

 Repeat all steps for a jellyfish dome hat tentacle ½ scale.

Step 21: Assembly

Take the long flap on P1 on the bottom and insert it into the incision on the next side.

Step 22: Insert

Insert it about 2" and then fold in back to lock it into place.

Step 23: Fold Back

Repeat steps 1 and 2, 7 times until you have a dome shape like a jellyfish.

Step 24: Top

Take the tentacle (P2) and insert it into the top incision above the long flap.

Step 25: Middle

Pop it back out the other incision that is directly in the middle of the bottom flap.

Step 26: Bottom

Insert tentacle into second incision in the middle of the horizontal flap and pull down.

Step 27: Repeat

Repeat steps 4 and 5, 7 times for all the tentacles.

Step 28: Excess

(Optional) Cut excess flap on the very bottom as it is unnecessary.

Step 29: Hat

Repeat all steps for the jellyfish hat.