TWM Home Main Indexes Main Indexes What's New At TWM Search TWM Main Indexes


Surface Tension and Water Drops
From "Microsmos"

Subject:     Science/Physics/Surface Tension & Water Drops

Grades:     K - 12.

Description:     This snippet shows examples of water drops forming and falling as rain.

The film consists of many extraordinarily beautiful shots of the surprising world of insects. There is almost no narration.

Benefits:     These snippets show insects in their natural environment and clearly show symbiosis and predation. They will interest students and enhance any biology class at any grade level.

Using the Snippet in Class:     Teachers can simply start the film at the beginning and play it until the end of the snippet on ladybugs, ants and aphids. It takes about 13 minutes. On the way to the scenes of the bees, the class will be shown short sequences of many other insects.

On the way to the episode with the bees and the flowers, the class will see many beautiful shots of other insects. Some briefly illustrate biological processes such as a butterfly emerging from a cocoon. Feel free to comment on any of these or on the types of insects shown.

Length and Location: The snippet starts at the beginning of the film and ends approximately fifteen minutes into the film. If you also show the spider eating the grasshopper the snippet will be approximately 21 minutes long.

Possible Problems:     Occasionally insects are shown eating other insects, mating with other insects and fighting with other insects. Between the segment of the ants, ladybugs and aphids there is a fabulous segment of what appears to be snails mating. This might gross out younger classes. There is nothing that should disturb a child of any age. However, adults should view any film before they show it to children and make up their own mind.

Why not use the whole movie? There is no reason not to use this film other than the fact that young minds might not have the attention span for the whole movie.

Surface Tension

Click here for a short clip of water dropping from a faucet. The image consists of 18 individual images, out of a series of approximately 300 images. The surface tension of the water inside the faucet holds the drop in and is responsible for the elongated shape at the beginning. Once pressure or gravity forces the drop free, and it falls, surface tension forces it into its spherical shape. See -- The animation is not a series of the same drop, but different pictures of different drops arranged to make them look like a series of pictures of one drop.

Building Vocabulary: symbiotic, predatory.

Teachers who want parental permission to show this movie can use TWM's Movie Permission Slip.

Reminder: Obtain all required permissions from your school administration before showing this snippet.

This film is available from

TWM grants free limited licenses to copy TWM curriculum materials only to educators in public or non-profit schools and to parents trying to help educate their children. See TWM's Terms of Use for a full description of the free licenses and limits on the rights of others to copy TWM.