view a plan
This is a DNA lesson called “Breaking The Code”
4, 5, 6
Science: Breaking the Code by: Kathleen O'Connell Grade Level: 4-6
Purpose: To introduce the concept of DNA and its transcription into RNA and translation into proteins.
Age: I did it with 4th graders, and they understood it pretty well, but it would be good with 5th and 6th graders too I think
Materials: Microsoft Word--WingDings font (all caps) popsicle sticks paint paintbrushes little toys (I used Bart Simpson chess pieces) glue clay
Procedure: The teacher must make the code. I used WingDings because each symbol corresponds to a letter and you can easily go back and forth between the code and English to make sure you don’t have any typos. Write directions to build a shelter in code. The shelter that I built was made by gluing four popsicle sticks in a square. The square was filled in with other popsicle sticks to make a flat roof structure. Then, four large balls of clay were made. A popsicle stick was stuck into each ball. Then, a smaller clay ball was placed on top of the popsicle sticks and flattened a little bit. The roof was painted after the glue dried. The four clay-popsicle stick “barbells are placed at the four corners of a square with the small, flattened balls facing up. After the paint dries, the roof is placed on top of the small balls.
Not every coded set of directions should be the same. Mine all coded for using different colored clay and different colored paints. I also made one with a “mutation” in the code. Its directions did not say to fill the roof in with popsicle sticks, so the kids were left with an open square.
In class: First explain the basic principles: DNA is the genetic code, found in cell’s nucleus (draw picture…helpful if you have already discussed cells), code is “decoded” into RNA, RNA is read and translated chains of amino acids which make up proteins.
Then tell story behind project. I told them that Bart Simpson (the little chess pieces) was stuck in a huge rainstorm on a camping trip. He has all the materials and the directions to build a shelter, but he finds that the directions are in code. He does not know how to translate it, but we (the scientists) have the key (the key is which WingDings=which letter). The students must decode the directions and build the shelter for Bart. I warned them that not every shelter would be the same. They worked in groups of four.
When the shelters are complete, draw parallels from the project to the prior discussion on DNA (the coded message is DNA, the English message is RNA, the materials are the amino acids…or perhaps the proteins, and the shelter is the protein…or perhaps the whole organism). Point out the “mutated” shelter. Ask the scientists to figure out as a group where the problem is using a functional shelter as comparison. The students determined that it was not the fault of the students who made that shelter, they did not decode the message faultily or put it together wrong. They determined that the fault lay in the code itself. We talked about how this is a mutation and when mutations occur in genes (we had discussed genes earlier) they can cause the protein (or in this case the shelter) to not work the way it is supposed to. We discussed how this can cause many disorders, some more serious than others.
The group with the mutation got to do a little gene therapy on their shelter. They wanted a good shelter for Bart, so we corrected their code by comparing it with the code for the functional shelter, and then they finished their shelter.
Time: about 1 hour and 15 minutes counting discussions at beginning and end
Submitted by: Kathleen O'Connell '98 Williams College Williamstown, MA Performed at Brayton Elementary School, North Adams, MA