Making an Object Invisible!

Objects you will need:  One larger glass jar, one smaller glass jar, another jar with vegetable oil (I actually used olive oil) and a cookie sheet to catch any oil that might spill from pouring.

I based this lesson on 1 Timothy 1:17--

“Now unto the King eternal, immortal, invisible, the only wise God, be honour and glory for ever and ever. Amen.”

I wanted to help the children understand three of these words:

After explaining these three words, I wanted to focus the rest of the lesson on the meaning of INVISIBLE. So we talked about things that are invisible:

Radio waves. I brought a transistor radio and played it.  The radio waves are in the room but you cannot see them.

Sound waves.  Sound must travel through the air but you cannot see it.

Air.  Air itself is invisible.

Wind.  We can see the effects of the wind (tree branches waving, kite flying, sailboat being pushed along, etc.), but we cannot see the wind.

Stars.  During the day the stars are invisible even though they are there.

Gravity.  I showed the class an object falling. We can see it fall but we can't see gravity.

Some animals are invisible.  I showed the children these pictures of the Glasswinged Butterfly (pictures on left) and the European Eel (pictures on right):

We then discussed how angels can be present but we cannot see them.  The same is true of the devil and demons (evil angels). We talked more about how God is invisible.  He is real and He is present with us always, even though we cannot see Him.  The teacher could also talk about how God became flesh, took on a human body, and because of that He became visible.  People could see Jesus Christ, God's Son.

Now for the fun part.  "Children, do you think I can make something invisible?"  (They didn't think I could).  Hold up the small jar and ask the class if they can see it.  Everyone can see it; it's very visible.  Then put the small jar inside the larger glass jar. Hold it up and ask the children if they can see the smaller jar.  They still can see it inside the larger jar. It is not invisible.  Then pour the oil into the larger jar so that it fills the smaller jar and fills the larger jar to the point where the oil is about a half-inch or an inch over the smaller jar.  Amazingly, the smaller jar can no longer be seen.  It has become invisible.

Suggestion:  The teacher should try this at home before doing it in class to make sure it works.  It worked for me and it should work for you.  Glasses (made of clear glass) or glass flasks should work as well and may work even better than jars if you can find a large one and a small one.

--George Zeller

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