Vaccinated and Fascinated

How do vaccines work?


  • Understand how vaccines protect our bodies
  • Understand what an mRNA vaccine is

What Do I Do All Day?

Hi! I’m an immunologist – an allergy doctor! I help people who have trouble using their immune system to fight infection, but did you know that allergies and eczema have to do with your immune system? One part of my job is testing what allergies my patients have in the Allergy and Immunology department of the hospital by putting tiny amounts of allergens on their skin. I can tell you if you’re allergic to specific kinds of trees! I love helping people with allergies, it’s kind of like a mystery puzzle to solve!

Materials Needed:

  • Paper Plates
  • Pipe Cleaners
  • Liquid Glue or Hot Glue
  • Beads
  • Markers, colored pencils, and/or crayons
  • Paper clips – 4 different colors to represent adenine, uracil, guanine, and cytosine


Germs and the Immune System

  • Germs are organisms that can cause disease in the body (for example, E. coli)  
  • Most of the germs that make us sick are either bacteria or viruses  
  • Germs can get into the body through the nose, mouth, breaks in the skin, or eyes 
  • Once they are in the body, they can cause disease when they: 
    • Produce toxins (small poisons that can damage tissues and disable the immune system)
    • Increase their number by breeding rapidly and stopping the body from working properly 
    • Attack/damage a certain part of the body  
  • The body’s immune system helps fight off the germs. Different types of white blood cells have different roles in fighting germs: 
    • phagocytes destroy the invader organisms 
    • lymphocytes help the body remember the invaders  
  • Most of the time diseases caused by germs will go away after a day or so. Sometimes, the disease may be more serious and require treatment from medical professionals.  
  • Vaccines help introduce the body to different kinds of invader organisms so that the body can recognize them in case they ever come back later in life.  
  • The easiest way to stay safe from germs is by washing your hands using warm soap and water for at least 20 seconds
  • Germs are tiny little living things called organisms that can make us sick if they get into our bodies. They are so small you need a microscope to see them!  Most of the germs that can make us sick are viruses or bacteria.  
  • Your body has lots of built-in ways to fight germs – but sometimes, the germs spread and grow too fast and that’s when we get colds, coughs, or other sicknesses.  
  • Germs can spread in spit, sweat and blood – think coughs, sneezes, even breaths  
  • The best defense against germs is hand-washing! Warm soap and water can kill those germs that might make you sick. 


  • Vaccines are used to provide your body with immunity, the ability to resist, to certain diseases. Vaccines have increased our lifespan by 30 years and have largely eradicated certain diseases, like smallpox and polio. 
  • There are several different types of vaccines:     
    • Live-attenuated vaccines (use a weak form of the germ)
    • Inactivated vaccines (use a dead form of the germ)
    • Subunit, recombinant, polysaccharide, and conjugate vaccines (use only pieces of the germ)
    • Toxoid vaccines (use a toxin created by the germ)
    • Messenger RNA vaccines (a new type of vaccine that uses the mRNA of a germ; this is what we are using to battle Covid-19)
  • mRNA vaccines, like the vaccines used to combat the Coronavirus, give the cells in our bodies instructions to create copies of a protein found in the Coronavirus. Our cells then make copies of this protein and our bodies learn how to fight the genetic material, the mRNA, from the vaccine.
    • To ensure mRNA is transferred safely into our bodies, they are placed inside lipid nanoparticles. Otherwise known as solid lipid nanoparticles, lipid nanoparticles are spheres that are composed of lipids (fats) and are a new form of drug delivery system. In other words, lipid nanoparticles act as “bubble wrap” for mRNA in Messenger RNA vaccines.
  • Vaccinations provide protection from 16 different communicable diseases in the United States.


  • Coronavirus is a word you might have heard lately at school, at home, or on the T.V. The coronavirus is a newly discovered virus that doctors are still learning about. 
    • Coronavirus is nicknamed “COVID-19,” but that just stands for coronavirus disease 2019.  
  • This virus has made a lot of people sick lately, but scientists and doctors think most people will be okay, especially kids.  
  • Most people who get sick just feel like they have a really bad cold and need to stay home for a while, but some people have gotten really sick and need the help of doctors. Doctors and health professionals are working hard to help everyone stay healthy!  
  • You are probably staying home for a while and won’t be able to go back to school. Doctors and researchers think this is the best way to make sure lots of people stay healthy, and the germs don’t get spread to you or your friends.  It’s totally normal to be feeling worried or stressed out about the coronavirus. When routines (things we do every day) have to change, it makes a lot of people feel worried.  
  • Make sure you talk about these feelings with your family – they’re probably feeling the same way. We can do research together to be sure we have the most updated true information.

Please visit for updated information, resources, and tips. Always talk to your doctor for professional medical opinions. In some cases, this activity might bring up challenging topics or discussions, or may cause children to feel worried. This lesson should not be used as a replacement for professional psychological care. For 24/7 free, confidential nationwide support finding resources to manage stress, please call 1-800-662-HELP (4357).

Activity Plan

  1. Connect to prior knowledge:
    • Ask: Have you ever wondered why we get shots when we go to the doctor? Why do we do that?
    • Explain: We get shots to protect our bodies from diseases and foreign germs. These shots are called vaccines. Scientists have different methods for creating different vaccines and have recently created a new method to fight Covid-19. This new method, used by Moderna and Pfizer, involves putting mRNA, bits of genetic information similar to DNA, into our bodies through a shot. Our bodies will then use this information to learn how to fight Covid-19.
    • Ask: How do we protect breakable or important items like Christmas ornaments or a favorite toy while moving or going on a trip? How do you think we get mRNA into our bodies safely?
    • Explain: Just like how we bubble wrap and protect special things to ensure they get to their destination safely, scientists protect the mRNA by placing it in a Lipid Nanoparticle
  2. Create the Lipid Nanoparticle
    1. Using a marker, colored pencil, or crayon, trace along the ridges of the plate leaving a gap in the middle.
  3. Glue beads to the outer edge of the plate, connecting to two ridged lines.
  4. Glue beads to the inner edge of the ridged portion of the plate, connecting to two ridged lines. See image below for reference.

3. Create the mRNA
1. Take a pipe cleaner, a few beads, and a few of the differently colored paper clips. Explain that the paper clips are 4 different colors because there are four different proteins that make up mRNA: adenine, uracil, guanine, and cytosine. The order of these proteins determines the makeup of the mRNA.
2. Then, string a bead, a paper clip, and then bead onto the pipe cleaner. Continue alternating between bead and paper clip until the pipe cleaner is complete. Finish the mRNA strand with a bead. Be sure to secure the initial and final bead onto the pipe cleaner to ensure the paper clips and beads do not fall off. Your mRNA should look something like the below image.

4. Place the mRNA in the middle of the plate. Do not glue into place and demonstrate that the mRNA travels from the Lipid Nanoparticle into our bodies and then to our cells in order to replicate the Covid-19 protein that our bodies need to learn to fight.

Book Connections:

Baby Medical School: Vaccines: A Human Body Book for Kids (Baby University)

Video Resources: