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Procedure

Compass

1. Make an X in the center of the outside bottom of the bowl using electrical tape.
2. Fill the bowl with enough water (about half way) so that the compass paperclip will be able to move.
3. Cut a piece of thread about twice as long as the height of the water in the bowl. Tie one end loosely to a packing peanut. Tie the other end to a paper clip. Make sure the thread is neither too short (it is too short if it pulls the peanut under the water) nor too long (the thread and anchor allows the peanut to float to the sides of the bowl).
4. Magnetize the compass "needle" (straight pin) by stroking it one direction with the magnet (you will need to stroke it at least 20 times).
5. Stick the compass needle (straight pin) through the center of a packing peanut with the paperclip "anchor."
6. Place the pin/peanut/paperclip assembly into the bowl of water (see Figure 1). What happens? (The magnetized straight pin should rotate to be oriented north/south. Verify orientation with a real compass.) Have students record answers on their Find Your Own Direction Worksheets.
7. Have students walk around the room with the compass they made. What happens to the compass needle as you move about the room? (Answer: it should always rotate so that it is pointed north/south.) Have students record answers on their worksheets.
8. Hold the compass flat near the top of any iron or steel object in the room (the most common steel objects in a classroom are filing cabinets and garbage cans, but any object than contains steel — small refrigerators or radiators, for example — will work). What happens when the compass is near the topmost part of the object? (Answer: the needle should point at the object.) Move the compass down to the bottom of the steel object, still holding it flat. What happens? (Answer: the needle should flip around 180 degrees.)

Astrolabe

Step #1 – Print and cut out this Quadrant Printable or create your own.

Step #2 – Using a glue stick, glue the quadrant onto some cardboard or heavy paper.

Step #3 – Using a nail, poke a hole through the paper and cardboard where hole punch is labeled.

Step #4 – Attach your string to the quadrant on one end and attach the washer to the other end.

Step #5 – Next, glue your straw to the part that says, Glue straw here.

Materials List

Each group needs:

1. thread, ~12 inches (~30 cm)
2. 1 or more packing peanuts (the non-biodegradable type) or other small pieces of Styrofoam™
3. 1 plastic bowl (such as a margarine tub) large enough to accommodate the needle
4. 1 paper clip
5. 2 common straight pins
6. water
7. Find Your Own Direction Worksheet, one per student

To share with the entire class:

• a few strong magnets
• a few hand compasses
• red or black electrical tape, 1 roll