Tutor Information

Week 15

Science Experiments

Sinkers # 127

Purpose: To demonstrate how placer ore deposits form.


Materials: Glass jar with lid

Tap water

1 cup soil

5 paper clips


Procedure: Fill jar half full with water (Director will complete).

Add the soil and paper clips

Close lid and shake jar vigorously.

Allow jar to stand undisturbed for 5 minutes.


Results: The paper clips will fall quickly to the bottom of the jar, and the slower moving soil settles on top of the paper clips.


Why? Most of the soil falls more slowly that the heavier paper clips, and thus a layer of soil forms on top of the paper clips. In nature, rain beats on top of the soil, shaking and softening it. The heavier materials in this wet mixture sink lower and lower as the years pass. Heavy grains of metal continue to sink until they reach a hard rock layer. Particles of metal that combine in this method are called placer ore deposits.



Prints # 128

Purpose: To determine how fossils were preserved.


Materials: Modeling clay for each child

Paper plate for each child

Assorted seashells

Petroleum jelly (in a cup for class to share)

Plastic spoons

Cup w/plaster of paris

Tap water


Procedure: Place a piece of clay on the paper plate.

Rub the outside of a seashell with petroleum jelly.

Press the seashell into the clay.

Carefully remove the seashell so that a clear imprint of the shell remains in the

Clay.

Mix 2 spoons of water with plaster in cup.

Pour the plaster mixture into the imprint in the clay.

Allow the plaster to harden, about 15-20 minutes.

Separate the clay from the plaster mold.


Results: The clay has an imprint of the outside of the shell, and the plaster looks like the outside of the shell.


Why? The layer of clay and the plaster are both examples of fossils (any impression or trace of organisms from past geological times). The clay represents the soft mud of ancient times. Organisms made imprints in the mud. If nothing collected in the prints, the mud dried, forming what is now called a cast fossil. When sediments filled the imprint, a sedimentary rock formed with the print of the organism on the outside. This type of fossil is called a mold fossil.

Fine Arts - Angelico (AHN-JEH-LIH-KO)

Fra Angelico painted golden halos around a person's head to show an inner goodness shining out for everyone to see. Halos were often made with real gold, not with gold paint.


Painting with Silver Leaf


Materials: Black construction paper

Pencil (tutor bin)

Aluminum foil

Scissors (tutor bin)

White glue

Oil pastels


Process: Sketch a large design on the construction paper. Ideas include angels with halos, fish with shiny scales, a robot, crown with jewels, star or moon, abstract design of foil and color.


Cut pieces of aluminum foil to fit some areas in the drawing and glue them down.


Use oil pastels to fill in color around the shiny areas.


Variation: Metallic markers will be available for students to use. These are very expensive and I have only 10 markers total (2 for each class).