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Idaho 4-H Presents: Stem Wars. Show us spectacular! University of Idaho Extension 4-H

Test your skills and creativity

April through July 2021 is new STEM Wars! challenge. Individual or teams may participate by submitting videos of their spectacular attempts at becoming fan favorites for each challenge. We want to see explosions, crashes, laughter and magnificent feats in innovation. Make sure to check UI Extension 4-H Robotics to watch submitted videos. Are you up for the challenge?

If you have questions or need further information about STEM or the STEM Wars! challenges please contact Claire Sponseller at


4-H Challenge 1 — Toothpick Bridge

Launch: March 2021
Favorites announced around April 15, 2021

4-H Challenge 2 — Build a Volcano

Details announced middle of April
Launch: April 15, 2021
Favorites announced around June 1, 2021

4-H Challenge 3 — Egg Drop

Details announced end of May
Launch: June 1, 2021
Favorites announced around July 15, 2021

Compilation Video

Winning videos will be compiled and shared during National 4-H Week, October 2021

Challenge 1 — Toothpick Bridge

  • Materials needed — Round toothpicks White glue
  • Challenge — Create a video that will showcase your skills at engineering and design! Build a bridge that can hold at least one 16 oz bottle of water for five seconds. Then try to see how many more bottles of water it can hold. Each bottle of water must last at least five seconds on the bridge.
  • Bridge Dimensions — Unsupported span must be 12 inches in order to qualify test
  • No toothpicks can be broken
  • Registration — Submit your information and video through the Google registration form at

Challenge 2 — Build a Volcano

  • Make sure you create a safe environment; we suggest outside as it will make a mess
  • Keep the materials you use to household items, nothing special needs to be ordered — in your video upload please list the ingredients used
  • Maximum of one quart capacity in the "magma chamber"
  • No toothpicks can be broken
  • Registration — Submit your information and video through the Google site for Challenge 2 beginning April 15, 2021 at:

Submission Details

  • First name and/or team name. For team registrations, when you register please include what name video will be uploaded under
  • Confirmation meeting "magma chamber" capacity
  • Details about your build (height, weight, etc.)
  • Include description/overview about video. Please include the time if something spectacular happens that people will want to fast-forward to

Ways to make your video a favorite:

  • The artistic flair and realism of your design
  • Telling a story through your design
  • Height of eruption
  • Creating different features to your volcano (can the top come off?)
  • Best lava (color or other special features)
  • Largest explosion
  • Smoking volcano

4-H Headquarters

University of Idaho Extension 4-H Youth Development

Physical Address:
Mary E. Forney Hall
1210 Blake Avenue, Room 206

Mailing Address:
UI Extension 4-H Youth Development
University of Idaho
875 Perimeter Drive, MS 3015
Moscow, ID 83844-3015

Phone: 208-885-6321

Fax: 208-885-4637


Web: 4-H Youth Development

4-H on Google Maps