When the shadows come out to play

POULSBO — Why can three shadows be seen if only two lights are shining on a single object?

POULSBO — Why can three shadows be seen if only two lights are shining on a single object?

While many adults may have forgotten the answer, Beverly Godfrey’s first-grade science students at Vinland Elementary know the reason.

The budding scientists delved into the world of lights and shadows this year as they experimented with flashlights, lights and colored lights.

The newcomers to the scientific field learned how to make light bounce, how a shadow changes size, the property of light and most importantly they experienced the scientific process.

“They were able to work through the whole scientific process themselves. They were really like little scientists,” Godfrey said.

Godfrey said at the start of the lights and shadows unit the small scientists didn’t know that a shadow gets bigger as it gets closer to the light, and they learned that a shadow is an object blocking the light.

Both novel ideas for the 6 and 7 year olds, Godfrey said.

“Those are concepts they have to think about,” she said. “They only believe what they can see and they are just starting to believe in something even though they can’t see it.”

On Tuesday the now light-bending and light-manipulating experts gave a show of lights for everyone else to see.

First the lights were turned off, but Godfrey was armed with four high-powered, hand-held lights; red, orange, blue and white. The lights are a new asset to the unit this year as Godfrey was awarded a North Kitsap Education Foundation mini grant.

Next a group of students made a row in front of the room, facing the white board.

It was time for an appearance from the shadows.

“How do we get a colored shadow?” Godfrey asked.

A few students said to shine a blue light and a blue shadow would appear, but the majority said shining a blue light would make a black shadow.

The latter is right.

But when Godfrey shined a blue and white light on the students, three shadows were cast on the wall — blue, orange and black.

“A real ‘a ha moment’ was learning we need two lights together to get a colored shadow,” Godfrey said.

The same trial was repeated with the red and orange lights and the results were also the same.

As the grand finale all the lights came out to play, without the white light.

It was time to figure out how many shadows and what colors would be produced.

The guesses: all black, four shadows, blue and red and five colors and four shadows.

The results: The orange light produced one black shadow, adding in the blue light created three shadows; orange, blue and black, combining the red light produced five shadows and five colors and once the white light was thrown into the mix, six shadows danced on the wall.

The students and shadows cheered and clapped at the showing.

When asked how that happened, Godfrey — who doesn’t like to give away her secrets — evaded a response as she said, “It’s my job to get kids asking questions more than me giving answers.

“That’s what science is all about. It’s helping kids ask more questions so they have a reason to learn more. It’s experiences like this that really get kids excited about learning. It has nothing to do about testing. It’s all about I do and I understand.”

While Godfrey’s students understood all that was going on with the lights and shadows, this student needed a little scientific help to figure it all out.

And the reason two lights, one white and one colored, produce three shadows is: When both lights are blocked, or in other words where the shadows intersect, the shadows are gray or black. Away from the intersection, when the colored light is blocked the shadows are greenish, and when the white light is blocked the shadows assume the color of the light being shown.

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