Valentine’s Day science experiments for kids

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The good folks at Noggin Builders can turn any day into a learning day.

They have classes and camps for curious kids up to age 14.

They're making this week fun with some Valentine's Day science.

For more information, go to:

Fizzy Treasures

  • 2 tsp Citric acid
  • 1 tsp Baking soda
  • 1 tsp Cornstarch
  • Oil
  • Oil based coloring, if desired
    * Makes 1 Treasure *

Combine the dry ingredients (citric acid, baking soda & cornstarch). Add a SMALL amount of oil and mix. The consistency should be similar to damp sand, and the mixture should hold together when pressed firmly.

Shape as desired and allow Fizzy Treasures to dry overnight. Place in an airtight container when dry. Use water to see the treasure fizz!

What’s the Science? Citric acid and baking soda create an acid-base chemical reaction.Because they are both solids to start, they don’t interact. When we add the water, the acid and base molecules can come in contact with each other and the reaction (and fizzying!) begins.

Secret Valentine Messages

  • Citric acid mixed with water (or another acid like lemon juice or vinegar)
  • Thick paper, like card stock
  • Q-tips
  • Cabbage Indicator (see below)
  • Cotton balls

To make cabbage indicator:
• Tear purple cabbage leaves into small pieces and place in a heat-safe bowl
• Heat water to a boil and fill the bowl, covering the cabbage pieces
• Let the bowl stand until the water reaches room temperature
• Pour the solution through a strainer and into a clean jar

Dip a Q-tip in the acid and write a secret message on thick paper. Let the message dry completely. Dip a cotton ball in cabbage indicator and lightly dab onto the secret message to reveal what it says!

What’s the Science? Cabbage juice is a pH indicator - it changes color when it touches and acid or base. When the cabbie juice touches the dried acid, it turns bright pink. You can experiment with different kinds of liquids to write your secret message!

Crystal Hearts

  • Pipe cleaner
  • Sturdy glass jar, like mason jar
  • String
  • Pencil
  • Hot water, add coloring if desired
  • Borax
  • Spoon

Cut and shape a pipe cleaner into a heart - ensuring it can fit into the jar. Tie one end of the string to the pipe cleaner and the other end to the middle of a pencil.

Adding very hot water to the jar. Stir in borax until it will no longer dissolve.

Hang the pipe cleaner so that it's submerged in the borax solution, but not touching the bottom. Place the pencil across the top of the jar to hold the pipe cleaner in place (roll the pencil to take up slack in the string if necessary). Put the jar somewhere that it will not get bumped or moved while the crystals grow.

After the crystals have grown to the size you want, remove it from the jar!

What’s the Science? Hot water can hold more dissolved molecules than cool water can. As the
water cools, borax particles come


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