Knotted Bones

Your children can amaze their friends when they show off knotted bones from a chicken or turkey.

What You'll Need:

  • Goggles
  • Long, thin bone from a cooked chicken or turkey
  • Tall glass
  • Vinegar
  • Plastic wrap

knotty bones
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Your kids can amaze everyone with the knotty bones they'll make.


How to Make Knotted Bones:

Step 1: Make sure your kids put on their goggles. Have them place the bone into a tall glass filled with vinegar.

Safety First
Wear goggles to avoid getting vinegar in your eyes.


Step 2: Ask your children to cover the glass with plastic wrap so the house won't smell like a pickle factory.

Step 3: Have everyone observe the bone. Leave the bone alone for three days, then have your kids remove it from the vinegar. Make sure they notice how flexible the bone has become. If it is really flexible, proceed to the next step. Otherwise, have your kids pour out the old vinegar and fill the glass with new vinegar. Leave the bone alone for a few more days.

Step 4: Ask your kids to tie the bone into a knot. Tell them to allow the bone to dry. They can then show it to their friends, and see if their friends can explain how it happened.

What Happened?
The vinegar (acetic acid) dissolved the calcium in the bone. Calcium makes bones hard and strong. Without the calcium, the bones become rubbery and flexible.

Fun Fact
Bones contain four minerals to make them strong: calcium, phosphorous, magnesium, and manganese. Of these minerals, calcium is the most important. Calcium is found in milk, cheese, and green leafy vegetables.


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