GAK!

A rite of passage of childhood is definitely making some GAK!  Easy to make at home and the kids love squishing and stretching it around!  For those who are unfamiliar, GAK is a little different in consistency than slime and is made with Borax instead of starch.  Liquid starch is hard to find in the regular stores around here so GAK it is!  And it’s fun!

Here’s what you need to get started:

  • Container for mixing (we used an old yogurt container)
  • Borax
  • Food coloring (We use liquid watercolors instead)
  • 4 oz Glue bottle (I’ve used Elmer’s and the one from the dollar store.  They all work!)
  • Warm water (not hot!)
  • Measuring cup
  • Measuring spoon
  • Spoon for mixingIMG_7452

Empty the entire bottle of glue into your container.

IMG_7383Fill the glue bottle with water.  Place the cap on and shake it up a bit to mix.  Then empty it into the container with the glue.IMG_7384

Add some food color if you want.

Add 1/2 teaspoon of borax to 1/4 cup of warm water.  Mix well and add to the glue mixture.

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You will see that the mixture will start to blob up.  Mix it up and you will start seeing the GAK firm up.  It may look watery at first.  That’s ok.  The more you work with it, the more firm it gets.

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If there is any liquid left, just pour it out (in the garbage, not the sink!)

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See how stretchy it is!

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The tots enjoyed playing with it!

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They made hand prints with it too!  So much fun!

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We placed the GAK into a baggie to take home.  I actually have my son’s GAK from 6 months ago and it’s still good!

The Science behind the Activity:

Here’s my simplistic explanation: Glue is made of a polymer which is a long chain of the same molecules all linked up together.  When you add the borax, it links up with the molecules to form a more solid substance, hence the GAK.  A common analogy is if you have a chain with repeating metal links, that can be considered as the polymer.  When you add a bunch of magnets (borax) they all clump up together like the GAK or Silly Putty.

Follow this link to see where I got the idea from and more details about the science behind the experiment: http://www.stevespanglerscience.com/lab/experiments/glue-borax-gak/

 

 

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Homemade Bouncy Balls

My boys LOVE those bouncy balls that they get in goodie bags.  We have a million of them around our house (OK, maybe not a million, but they are always around somewhere around the house).  My littlest one loves crawling after them.

I’ve seen a lot of posts about making your own so we decided to try it.  Almost the same ingredients that we used to make GAK.

Here’s what you need to get started:

  • Two containers for mixing (we used a plastic cup and an old yogurt container)
  • Borax
  • Food coloring
  • Cornstarch
  • Glue
  • Warm water
  • Measuring cup
  • Measuring spoon
  • Spoon for mixing

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Add 1 Tbsp of cornstarch and 1/2 tsp borax to the cup.

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Add 1/4 cup warm water to the cornstarch/borax mixture.  Mix well.

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Add 1 Tbsp of liquid glue to a small container.  Add some food coloring to it if you’d like.  My superheroes always add color because, hey, colors make everything more fun!  Mix well with a spoon.  It will be sticky.

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Slowly add the cornstarch/borax/water mix to the glue. Mix until a blob forms.

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When it gets too hard to mix and the “blob” is no longer holding any more liquid, take it into your hands and roll it between your palms until is gets firm and circular.

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The superheroes compared it to a real bouncy ball they already had at home.

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They had fun bouncing it around and comparing the real bouncy ball to the one we made.

I will admit, it definitely does not bounce as well as the real ball and after a few bounces, it did flatten out a bit.  We just rolled it back up between our palms and it was round again and ready to play.  We will need to tweak this recipe to see if we can get it be a bit more bouncy.  But the boys had fun with it all the same.

The Science behind the Activity:

Follow this link to see where I got the idea from and more details about the experiment: http://www.pbs.org/parents/crafts-for-kids/super-bouncy-balls/

Rain in a Bottle

So we got some unexpected late summer rain out here.  When I say rain, I really mean drizzle.  In California where summer rain is rare especially during our drought, there are many happy people out today doing the rain dance!  So, what a great opportunity to show the superheroes how rain really forms.  This is a super easy experiment which pretty much uses ice and water.  No excuses!  Try this!

Here’s what you need to get started:

  • Clear bottle with a cap (We used a 1L water bottle, but any water bottle will do.)
  • Very warm water
  • Ice cubes
  • Scissors
  • Blue food coloring (optional)

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Cut the top third portion of the bottle with scissors.

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Add very warm water to the bottom portion of the bottle.  We added 2 drops of blue food coloring to mimic the ocean.  You can see the water evaporating on the sides already.

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Invert the top portion and fill it with ice.  Be sure to put the cap on so the cold water doesn’t drip out.

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Watch as the water begins to condense on the side.  My 5 year old had already learned this at school and used fancy science terms when I asked him what was going on.  He said, “Mummy, the blue water is evaporating and then dripping down when it gets cold from the ice.  I think it’s called conversation.”  Haha!  I corrected him that it was condensation 🙂

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See how easy that was.  And if you don’t have a plastic bottle, just use a clear bowl with a plate of ice on top.  It should still work.

The Science behind the Activity:

The warm water in the bottom begins to evaporate and turn to a gas.  When the gas molecules of water reach the cold ice, they cool down and turn back to liquid water and drip down the side, like rain.  The “foggy” air inside the bottle simulates how clouds form, although they will not form in this experiment.  In the atmosphere, water evaporates from the sea, oceans, land, etc… and condenses when it reaches the colder upper atmosphere.  This condensation causes clouds to form.  When the clouds get heavy enough, the water falls down to earth in the form of precipitation as rain or snow.

Follow this link to see where I got the idea from and more details about the experiment:http://msdsgarden.blogspot.com/2010/05/making-rain.html

Ooooh! Oobleck!

I can’t believe it’s taken me so long to make oobleck with my superheroes!  The first time I ever heard about it was during a teacher workshop at the Exploratorium in San Francisco and then I forgot about it for years.  Until this summer.  If you’ve never made this stuff before, YOU HAVE TO!  It is the coolest thing you have ever felt!  And it only requires ONE ingredient (besides water).  So open up your pantry and make some TODAY!

Here’s what you’ll need to get started:

  • Cornstarch
  • Water
  • Food coloring (optional)
  • Shallow bin or rimmed baking sheet (we used a shallow Ikea bin)

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Add about 4 cups of cornstarch to the bin.  Let your superheroes touch it and feel it with their fingers.  Ask them how it feels.  We talked about the cornstarch being a solid.

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We talked about the water being a liquid and how it is different from a solid.

Then, we added about 2-2.5 cups of water.  Let your superheroes mix it with their hands. (You will know that you have the right consistency when you apply pressure to it, it will feel hard, but your fingers will still be able to glide easily in it, like water.

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This is the coolest thing you have ever felt!  It feel like clay when you pick it up.  But then turns into liquid immediately.  Try making a ball.  The picture on the left is me trying to make a ball.  When I opened my hand, it just oozed out!  The boys tried to scrape it off the bottom of the bin but it crumbled and then liquified.  We discussed whether they thought this was a solid or a liquid.

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Then we decided to kick it up another notch. Food coloring!

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The superheroes REALLY loved this part.  We added red.  And then we added some green.

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This was so much fun!  My oldest superhero said it felt like he was wearing a glove.  Even Daddy stopped by to check out the fun and was mesmerized by the oobleck!  And as it dripped down, it left a thin film on our hands which we easily scraped off.  It washes off immediately and easily with some water.  We will definitely be doing this again!

**NOTE** Do NOT pour the oobleck down the drain! Either throw it in the trash OR let the water evaporate and re-use the cornstarch to make another batch of oobleck.

The Science behind the Activity:

Oobleck is a pressure-dependent substance (Non-Newtonian fluid, for you science buffs) much like quicksand.  Apply pressure to it and turns hard; release and it liquifies.  By applying pressure, you force the cornstarch particles together and it reacts similar to clay (a solid) and by releasing the pressure, your hands can slide easily in between the particles.

And here’s a cool factoid: Oobleck gets its name from abook by Dr. Seuss called “Bartholomew and the Oobleck”

For a fabulous explanation of how oobleck works and more details, follow the link below:

https://www.exploratorium.edu/science_explorer/ooze.html