SI units are the modern version of the metric system. I remember learning metric units in grade school. Our teachers assured us that by the time we were adults we would all be using metric units in our everyday lives. As far as I can tell, imperial units are still alive and well here in the US, but in the field of science you will generally not see them. This is a good thing. Scientists must speak a common language, and measurement systems are a part of this language.

The letter scramble puzzle below features 41 words and definitions related to the International System of Units (SI Units). It was created using my SI Units word list on A2Z Puzzler. It includes the base units, such as meter and second, as well as the derived units, such as hertz and joule. It also  includes a number of prefixes like centi and kilo.

This printable puzzle is appropriate for high school science classes. If you want to make a similar puzzle, but simpler for grade school, use A2Z Puzzler to create a more limited list and create printable PDF puzzles from that.

 Astronomy Magazine: Astronomy for Kids

Astronomy Magazine has a page with articles of interest to young astronomers. For information about stars and constellations, check out Learn the Constellations and Celestial Navigation.

StarChild: A Learning Center for Young Astronomers

StarChild has some general resources about astronomy in a kid-friendly format. It is a project from a lab at NASA. Since I am looking at astronomy resources related to stars in this report, I recommend you look at the Level 1 Stars Page and the Level 2 Stars Page.

SkyMaps

SkyMaps provides free maps of the night sky for educational use.  There is a new map every month. They also have some information about using the maps which will be helpful for students and teachers who are just getting started in stargazing.

The Life Cycles of Stars

Learn how stars are born, live, and die. Includes some hands on activities at the bottom of the page for further astronomy exploration. These include models of different types of stars using tissue paper and a black hole model. From the Goddard Space Flight Center at NASA.

 The Constellations and Their Stars

This site includes a list of all the named stars and a list of constellations. If you click on one, you can learn more about the star or constellation with some viewing information. You have to learn your way around the site, but there is some very useful information here.

 All About Stars

Finally, check out my All About Stars pinboard on Pinterest. I’ll keep adding astronomy resources there as I find them. You can see the latest pins to the board below.

• 

  People have been gaz
• 

  It’s not always easy
• 

  To help find your wa
• 

  A star wheel will he
• 

  Learn the Constellat
• 

  A Child’s Introducti
• 

  Most people recogniz
• 

  Stars in a jar. Glow
• 

  If you are planning

One use for this technology - prosthetics. A prosthetic is an artificial body part, such as an arm or a leg. Prosthetics often stand out and can make some users self conscious. A prosthetic which blends in better would be a tremendous improvement.

Read the robot and then use the information to start a discussion about automation and its uses.

Read about robot camoflauge in  Color-changing robot

What questions come to mind after reading the article? Here are some examples:

• What other uses might be found for this technology?
• Do you think robots will become more common?
• If you could design a robot, what is the one thing you would want it to do?
• Does automation play a positive role in society or does it separate us from the natural world?

The reasoning behind this theory is that a spoon acts as a heat sink, conducting heat away from the drink. Heat sinks are commonly used in machinery and electronic devices, to prevent overheating. Since metal is a good conductor of heat, the heat travels away from the device or machine. Heat sinks are often designed like fins, to provide a lot of surface area for the transfer of heat to the surrounding air.

Science Experiment: Spoon as a Heat Sink

Materials

• two identical coffee cups or mugs
• hot water
• two identical thermometers
• masking tap
• metal spoon
• clock or stopwatch
• paper and pencil

Procedure

1. Label the thermometers 1 and 2 with the masking tape. (Do this so you can still read the temperature.
2. Leave the thermometers at room temperature for five minutes.
3. Look at the temperature on each. This is room temperature. They should be the same. If they are not, then you should take the difference into account when measuring the temperature later.
4. Label the cups 1 and 2 with the tape.
5. Fill the two cups to the same level with hot water from the same source. The cups must have identical amounts of liquid and the liquid must start at the same temperature.
6. Put thermometer 1 in cup 1 and put thermometer 2 in cup 2.
7. Put a metal spoon in cup 1.
8. Read the temperature of each cup every minute and write it down.
9. Continue until the liquid in the cups reaches room temperature.
10. Look at your data and try to determine if putting the spoon in the cup made the liquid cool faster.

Notes

Don’t be disappointed if there is not a difference between the two temperatures. A spoon is not really designed to be a heat sink. This experiment might really prove that you shouldn’t believe everything you hear.

There is some yuck factor here, so if you are squeamish about eyeballs, you might not want to look at it. But for some kids, the gross image will be a great discussion starter. Try asking some questions like

• What sort of animal do you think this eyeball might be from?
• What sort of tests might scientists do to learn more?
• What might have happened to this creature?
• How far away could this eyeball have drifted from

Science is all about questions and curiosity. The beginning of science knowledge is looking at the unknown and wondering what or why.

See the story and video: Huge eyeball from unknown creature washes ashore on Florida beach

Update:

The mystery has been solved! So where did it come from? Find out in this article from Deep Sea News.

You can do this simple sound wave demonstration with common household objects. You will need a partner to hold the candle for you.

Can Sound Waves Blow Out a Candle?

Materials

• 1 liter plastic bottle
• scissors or knife
• plastic wrap
• duct tape
• small candle
• matches

Procedure

1. Remove the cap from the bottle if it has one.
2. Cut the base off of the bottom of the bottle with a knife or scissors. Watch for sharp edges.
3. Cover the part where the bottom was with plastic wrap. The wrap should be taut.
4. Secure the wrap with the duct tape.
5. Light the candle.
6. Point the neck of the bottle (where the cap was) at the flame, a few inches away.
7. Give the plastic wrap a strong tap with your finger. You should see an effect on the flame.

Fooling the Mind’s Eye

Optical Illusions – Circles from Lines

Materials

• Index card
• Pencil
• Ruler
• Pin

Instructions

1. Using a pencil and a ruler, draw four dark lines on a blank index card, as shown in the image at the bottom of the article.
2. Insert a long pin in the middle of the card – approximately where the dark dot is shown in the image.
3. Hold the pin steady and spin the card. What do you see?

Explanation

You should see two concentric circles.

There is a location on each line which forms the smallest circle while the card is spinning. Because this circle is being traced more frequently while the card is spinning, it appears darker, creating the circles you perceive.

Many students will find it difficult to detect pulse using the traditional method of holding their fingers to a pulse point. They might find this method easier. It uses a match and a thumbtack to create a visual indicator of the pulse.

Homemade Pulse Rate Detector

Materials

• Flat thumb tack
• Large wooden match
• Watch or clock with a second hand

Procedure

1. Stick the thumb tack into the base of the match.
2. Wrest your arm on a table, with the palm of your hand facing up.
3. Place the flat thumbtack on the pulse point your wrist, with the match pointing up.
4. The match should move slightly, almost like a metronome. If it is not moving, you haven’t found the correct location. Try moving it.
5. Using you watch, count the number of times the match pulses in 15 seconds.
6. Multiply by four to get your pulse rate (heartbeats per minute).

The basis for this science fair project is that opposites attract. Two objects with opposite charges (a positive and a negative) will be drawn toward each other. Two objects with the same charge (both positive or both negative) will push away from each other. A similar concept can be observed with magnetic poles.

Science Fair Projects – Jumping Cereal

Materials

• Puffed wheat cereal
• Shallow dish
• Plastic comb
• Small piece of wool material
• Clear plastic toothbrush box

Instructions

1. Put a few pieces of the cereal in the dish.
2. Rub the comb with the wool for about 20 seconds.
3. Pass the comb over the cereal in the dish. (It should stick.)
4. Wait about 30 seconds and observe what happens.
5. Place a few pieces of the cereal in the toothbrush box and close it.
6. Rub the box with the wool for about 20 seconds.
7. Observe the cereal in the box

What is happening

Normally, the comb and the box are neutral. They have the same number of electrons (negative charge) and protons (positive charge). But electrons can jump around, while protons are fixed in place.

When you rub the plastic objects with the wool, electrons transfer from the cloth to the plastic object. The plastic becomes negatively charged.

The pieces of cereal are neutral. When they are near the negatively charged comb or plastic box, the protons in the cereal are attracted and the cereal sticks to the plastic. But after a short amount of time (30 seconds or so) some of the electrons move from the plastic to the cereal, and each has a slight negative charge. This causes the plastic and the cereal to be repelled from each other.

So with the comb, the cereal is first attracted to the comb and then falls off. With the enclosed toothbrush case, the cereal first sticks to the walls and then bounces off.

For more ideas, see Awesome Experiments in Electricity & Magnetism