Eggs are an incredible adaptation that allow birds to stay light and able to fly while their babies are growing. Bird eggs are covered in a shell with lots of tiny holes. These allow air and moisture to pass through. Eggs are also covered in a coating that keeps out bacteria and dust.
Place the egg in your hand (take off any rings first). Squeeze the egg with even pressure. Does it break?
Now (over the sink or outdoors) squeeze the egg with just two fingers. Did it break?
What will happen:
The shape of an egg makes it very strong to even pressure. Even an adult squeezing it can’t break the shell.
When uneven pressure is put on the thin shell, the egg cracks easily.
When a bird sits on an egg to incubate it, the pressure is evenly distributed on the shell and the egg can easily support the bird. When a chick is ready to hatch, it pushes on just a small part of the shell with its egg tooth and the shell will crack to allow the bird to hatch.
A drinking glass
Place the egg in a glass and cover with household vinegar. Wait about 24 hours, pour the vinegar out and replace with fresh vinegar. Wait a full week and then take the egg out.
What will happen:
The shell is made of calcium carbonate, which dissolves in acetic acid. The vinegar will dissolve the shell, leaving the semipermeable membrane intact. The yolk and white will still be contained in the soft membrane, so it will look like an egg, but will be squishy when touched.
February’s STEAM at Home program featured Awesome Architecture and fun building activities. We learned that x-bracing (seen here on the John Hancock Center in Chicago) is one way that helps keep buildings straight and tall when wind blows on them. X-braces and shear walls collect wind forces and carry them to the foundation. Build your own braced tower at home with a few simple materials! Idea and images from Building Structures and Towers by Tammy Enz.
mini marshmallows (the book shows gumdrops, but we used marshmallows)
Break 4 noodles in half and make sure they are roughly the same length. Put marshmallows in the corners to connect them into 2 squares.
Break off about 1 inch from 4 more noodles and use these to connect your 2 squares. What happens when you push on the tower?
Add 2 noodles to one side make an X. Repeat on all 4 sides of your tower. Try pushing again. Now what happens?
As the marshmallows harden, your structure will get even stronger. What other structures can you build?
Winter is a great time to bake bread. While it takes time to rise, the hands-on time of baking bread is minimal. Helping in the kitchen is useful for reinforcing following directions, practice with numbers, and is way to spend time with kids while bring productive.
This recipe is from Kid Chef Bakes, the kids cookbook for aspiring bakers, by Lisa Huff. It makes two loaves of white sandwich bread.
Stand mixer or large bowl
2 loaf pans (8 ½ by 4 ½, by 2 ½)
Pastry brush (optional)
2 cups warm milk (2% or whole is best, 105-115° f)
2 T sugar
1 (1/4-ounce) envelope active dry yeast
2 T butter at room temperature
1 T vegetable oil
Butter for greasing pans
Prepare the Yeast:
In the bowl of a stand mixer with the hook attachment, or a large bowl using a spoon, mix the yeast, milk, and sugar. Let stand for 5 min.
Combine the Ingredients:
Add the 2 T butter, 4 c flour, and salt to the yeast mixture. Mix on low with the hook attachment until well blended. Add more flour as needed, a little at a time, until the dough forms. Raise the speed to medium and continue to knead for 4-6 minutes or until the dough is elastic. Alternatively, mix the flour in by hand and knead by hand for about 8 minutes or until the dough is smooth and elastic.
Let it Rise:
Grease a large bowl with oil. Add the dough and turn to coat, then cover with plastic wrap. Place in a warm place to double in size, about 1 hour (or more if your house is cool). Tip the dough out, split it, and form two loaves. Please each loaf in a greased loaf pan. Allow to rise again for about 30 min.
Preheat the oven to 350° F.
Bake for 30-40 minutes or until brown and hollow sounding (bread should be about 200° F in the center when baked.) Cool slightly and then tip out onto a cooling rack. Cut when cool.
If you are looking for something to do while your bread is rising, try making butter in a jar. All you need is heavy cream and a jar. Try this recipe: How to Make Homemade Butter
To learn more about this holiday, we went to PebbleGo, accessible through the library website here.
Hanukkah is a Jewish holiday taking place for eight nights. This year, it started on Thursday, December 10 and ends Friday, December 18. It is also known as the Festival of Lights. Jewish people celebrate by lighting a candle on a menorah each night, eating special foods, and sometimes exchanging gifts. Many also like to play with a spinning top called a dreidel.
To celebrate, you can make your own dreidel and play a fun game to win treats of your choosing.
1. Draw equal triangles on your cardboard. You can do this by drawing two diagonal lines across the brown side of cardboard.
2. Draw the Hebrew letters below on each triangle.
3. Have a grownup poke a pencil in the middle of the cardboard square. Now you can spin it on the pencil tip!
Everyone gets the same amount of a small object- raisins, or stickers, or Hanukkah gelt (gold-foiled covered chocolate). You’ll be playing for these pieces.