Saturday, October 19, 2013

Op Art, Spheres and 3rd Graders

3rd graders started this lesson looking at an image of Victor Vasarely's Zebras on the Smartboard. You can see the painting and a brief article on Op Art here. We discussed the idea of "tricking the eye." Then we looked at some examples of other black and white op art, noticing how these lines all start from a point and the lines get wider as they move away from the point.
Students also started with a point and made their lines fatter at the edges of their squares (their squares measured 5 and a half inches).

Then we also looked at a tennis ball with a flashlight shining at it from one side, to see what the light source did to the ball, noticing where the lights and darks were. Students used three sizes of bottle lids to trace a large, medium and small circle. I had them draw a small sun with an arrow in the upper left hand corner to remind them where their light source was. I find this helps as children start shading.

 Students shaded the part of the circle furthest from their sun icon, using the side of their pencil lead and concentrating on curving their lines instead of going straight across the circle. They made that darkest part first and then tried to blend lighter grays as they went up. I had the kids hold a finger on the spot where the highlight would be so they would remember to keep that white. Of course, if it got colored they could always go back and erase to make that highlight.
What was tricky about this for students? Well, it is always a challenge for some to use the side of the pencil lead instead of the point. In the past, kids have wanted to shade using straight lines. This time, though most children followed the curve of the circle as they shaded -- yeah!! For some, it is hard to get the very darkest shades. After all, pressing hard and soft for different values takes practice.

I showed them how holding their spheres at arm's length helped them to see the 3-D effect. I saw a lot of children having their friends hold up their art across the table so they could appreciate the illusion. So fun to see kids cooperating!!

In part 2 of this lesson, students will add color to their spheres with crayons, cut them out and glue them (using size and position to give the illusion of depth) on their black and white op art piece. If we have enough time, some of the classes may add another colored element, too. I will share when these are done.


  1. These should look really cool when done! I like the clear steps - it's a pretty good challenge for grade 3, but I'm sure they can do it!

    1. I've done versions of this before with third graders, so I know it can be done. But you are right, the kids are hesitant about their ability as the tackle the first sphere. By the third one, though, they are full of confidence. It is fun to watch!!