Homeschool Science Corner ~ DNA Activities

All About DNA (including activities and free printables) | Homeschool Science CornerIn this week’s Homeschool Science Corner, we are sharing all about DNA!

What is DNA? 

DNA is the material that carries all the information about how a living thing will look and function. It is found in the nucleus of each of our cells and is unique to every individual. Its full name is deoxyribonucleic acid, which can be complicated to say, so we usually refer to it as DNA for short.

DNA is so tiny that it can not be seen unless we use a very powerful microscope. If we could see it we would see that it looks like a twisted ladder, which scientist refer to as the double helix.

The DNA ladder is composed of rungs that are made from two letters of the DNA alphabet. This alphabet consists of only 4 letters — A,T,G, and C. Each letter has a unique puzzle-like shape, which means that A and T fit with each other to form a rung on the ladder and G and C fit with each other to form a rung on the ladder.

As we read the DNA ladder, the letters combine to form 3-letter words called codons. Then, these codons combine to form sentences that we call genes. These genes are the basis for your chromosomes, which give your body a blueprint set of instructions for life.

Every human has 23 pairs of these DNA chromosomes that tell our body what to look like and what to do. We get one set of chromosomes from our mother and one set from our father. They determine whether your eyes will be blue or brown, what color your skin and hair will be, whether you will be a boy or girl and so much more.

Create your own DNA tower

You will need four different colors of LEGO bricks, at least six of each. In this activity, you are going to build several towers that are twelve rows high with the four different colors to see how different combinations you can make. Use the process as you build:

  1. Collect the four different colors of bricks, such as red, yellow, green and blue.Homeschool Science Corner ~ DNA
  2. Try to collect at least six of each color as well as different sizes of bricks.
  3. Decide what the color combinations will be. In other words, if you have red, yellow, green and blue. You can choose that red and yellow will go together, just like the A and T in DNA, and green and blue will go together, just like the G and C in DNA.
  4. Make a tower that has twelve rows. As you build, remember that a certain color can only pair with other color you have chosen, and that each row can only have two bricks. (Note – You should be able to come up with many different combinations, just like DNA.)
  5. Now that you have created a DNA ladder, use it to write a gene sentence. First, you will need to assign each color a letter. For example, red would be “R”, yellow would be “Y”, green would be “G”, and blue would be “B”.
  6. Next, write down your codons, or 3 letter words, from top to bottom and left to right.  As you work your way through the tower, you will create a unique gene-like sentence.

The sentence for the tower pictured above would be:


More DNA Activities

Here is another activity you can use to study DNA.

  • DNA extraction activity – This article from Marci at the Homeschool Scientist shares how you can extract DNA from a piece of fruit.

I hope that you find the explanation and activities in this post useful as you seek to share about DNA with your students! If you have any questions, please feel free to leave them in the comments below.

by Paige Hudson

Head to the Printables page to download some FREE science printables to use with this post – including a DNA Tower worksheet, narration page, and coloring page!


  1. Thanks for including me! I love the DNA tower idea! That is simple and effective.