Engineering design challenge: Blooming flower

Courtesy of: Engineers Nova Scotia 

In this design challenge, participants will make a flower that opens using a reel mechanism. A reel is a mechanism that uses a rotating cylinder to wind up or release something. Fishing rods often have a reel to release and pull in fish, and garden hoses can be kept tidy by winding them up on a reel. Even yoyos are reels! Ask participants to think about how they can use this as a way to open and close their flower and attract pollinators. 

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In this design challenge, participants will make a flower that opens using a reel mechanism. 


  • Paper
  • String
  • Straws (small)
  • Straws (large)
  • Scissors


Through this activity, participants will learn about pulleys and simple machines. Have participants think up some simple machines or provide examples.  

  1. Distribute a sheet of paper to each participant. Have them fold it into quarters and cut out a flower petal with a long stem. Demonstrate this for them and then have them use scissors to do the cutting.
  1. Cut equal lengths of string (you may want to precut these before participants arrive), one for each petal.
  1. Tape the string to the center of the petal near the top.
  1. Cut the small straws into smaller sections.
  1. Tape each of the petals to a small straw section on the same side as the string.
  1. Slide the string into the small straw.
  1. Tape the small straws to a larger straw.
  1. Using a piece of smaller straw, tape the ends of the strings to this piece.
  1. Wrap the string around the straw and demonstrate the flower blossoming.
  1. If extra time, allow them to decorate their flowers with markers and stickers.