-- Earth Balls --
I couldn't find the exact recipe I used with Hannah, so I had to rely on my memory. These days, I use the term "memory" very loosely, as there is precious little to draw from. So, I basically just stood in front of the pantry and picked some ingredients that looked vaguely familiar and sounded like they might moosh together to make a delicious earth. I mixed peanut butter, honey, and powdered sugar together until I had a firm dough, then I refrigerated it for about an hour.
We divided the dough into four equal parts and rolled each section into a ball.
Then, we used a sharp knife to carefully divide each ball in half, doing our best not to squish the ball. The peanut butter ball represents the mantle of the earth. The mantle is the thickest section of earth, stretching for thousands of miles. It is made of semi-solid rock.
We used the tip of a spoon to dig a well in the center of our "mantle".
Then, we dribbled in some homemade grape jelly to represent the outer core. The earth's outer core is made of metals like nickel and iron, and it is where the earth's magnetic field is formed.
We dropped in a chocolate chip to represent the inner core, since the inner core of the earth is made of solid metals.
At this point in the project, somebody probably should have checked on the baby to make sure she wasn't doing something she shouldn't be.
We carefully put the two halves of earth back together again, making sure the outer core didn't leak out, and smoothed earth back into a perfect sphere.
When I did this project with Hannah we used crunched up cookies for the earth's crust. I didn't have cookies today, so I settled for M&M's. With great attention to detail and a flair for authenticity, we carefully selected only blue and green candies, so it would look like the earth was covered in oceans and land. Honestly, the likeness was striking. :) So, the final step was to roll earth in the candy crumbs to make the crust, which is the layer of earth containing oceans, dirt, rocks, and mountains.
As a happy coincidence, the M&M's that were left were all the fall colors. Don't you just love it when tactile education and seasonal decorating collide all on the same day?? Brilliant.
We put our earth balls on a Star Wars plate, in keeping with the whole galaxy/outer space thing. Again, it really pays to be realistic with culinary science experiments. We set them to chill in the fridge, and now we have a dessert that will be out of this world. Oh, wait. Dessert IS this world. Whatever.
Earth balls. For when you have more time and peanut butter than you know what to do with. Also handy for helping small children to remember crust, mantle, inner core, outer core, and washing your hands after licking your fingers. Amen.
PS - Since the outer core of the earth provides a magnetic field surrounding our planet, we took the opportunity to make a homemade compass by magnetizing a needle and floating it on a piece of cork. Max checked the accuracy of our homemade compass against his real compass that his Papa gave him the night he became a boy scout. He hunted it down not just because he loves it and is sentimental about it, but also because math comes right after science, so we'll do whatever it takes to prolong science.