Alpha science classroom: Test the antibacterial effect of soap

Alpha science toys company knows kids like to explore something new in their growth process but they don’t like to wash hands and take a shower after being exposed to a lot of bacteria. Because kids have no clear idea of what harm and effect bacteria bring to human health. In the last two classes, Alpha science classroom helped kids know the different types and harms of bacteria and learned how to kill bacteria through the children’s science experiments on bacterial growth. Today, Alpha science classroom tells you how to remove bacteria with different types of soaps and makes kids know which one is the best way to kill bacteria. We can use Agar and Petri dishes to grow bacteria organisms and then do the science experiments for kids.

Alpha science classroom: soap antibacterial science experiments for kids materials 

1. Two (or more) Petri dishes

2. Sterile swabs

3. Agar

4. Blotter paper or other absorbent paper

5. Forceps or tweezers

6. Different kinds of hand cleaners: regular soap, antibacterial soap, dish soap, hand sanitizer

Alpha science classroom: Steps of antibacterial effect of soap science experiment for kids

1. Prepare the agar according to the directions on the label, then pour enough to cover the bottom of each petri dish. Cover the dishes and let them stand for about an hour until the agar has solidified again. (If you aren’t going to use them right away after they have cooled, store them upside down in the refrigerator.)

2. When your Petri dishes are ready, collect some bacteria from your hand or the hand of a volunteer. (Make sure the person hasn’t washed his or her hands too recently!) Do this by rubbing the sterile swab over the palm in a zigzag pattern.

3. Remove the cover from the petri dish and lightly rub the swab back and forth in a zigzag pattern on the agar. Turn the dish a quarter turn and zigzag again. Cover the dish and repeat steps two and three for the other dish, using a new sterile swab. Label the dishes “Test” and “Control.” (You may want to do more than one test dish, so you can compare the results.)

4. Cut the blotter paper into small “sensitivity squares.” Use permanent link to label the squares for the different types of hand cleaners you are going to test, e.g., “R” for regular soap, “A” for antibacterial soap, and “S” for hand sanitizer. Using tweezers, dip each square into the appropriate cleaner. Blot the excess cleaner on a paper towel and then place the squares on the agar in the “Test” dish. (Spread the squares out so there is the distance between them.) Add one square of plain blotter paper to test if blotter paper by itself has any effect. Don’t put any squares in the “Control” dish – this one will show you what the bacterial growth will look like without any soap.

5. Put the dishes in a dark, room-temperature place like a closet and leave them undisturbed for a few days.

Alpha science classroom: What happened to the science experiments for kids on the antibacterial effects of soap

The rate of bacteria growth in your dishes will depend on temperature and other factors. Check your cultures after a couple of days, but you’ll probably want to wait 5-7 days before recording your data. You will see multiple round dots of growth; these are bacteria colonies. There may be several types of bacteria growing in the dishes. Different types of colonies will have different colors and textures.

Alpha science classroom: Hand washing can prevent the harm of germs

Alpha science toys think kids should count and record the number of bacteria colonies in each dish for each soap test. To see how effective each soap was, divide the number of colonies in the test dish by the number of colonies in the control dish, then subtract the result from 1 and write the answer as a percentage. For example, if your control dish had 100 colonies and your soap test dish had 30, the soap eliminated 70% of the bacteria: 1 — (30 ÷ 100) = .7 = 70%

Alpha science toys let kids know there will be some bacteria on their hands when they touch an object each time. Bacteria can safely live on our skin, but if they enter through our mouths or become infected on cuts or scrapes, they can make us feel uncomfortable. That's one of the reasons why it's so important to wash our hands often.

Alpha science classroom: When should kids wash their hands to prevent the bacteria?

1. Before, during, and after food preparation

2. Before and after coming into contact with a sick person who has vomiting or has diarrhea

3. Before and after treating a cut or wound

4. After using the bathroom

5. After cleaning a child who has used the bathroom

6. After blowing your nose, coughing, or sneezing

7. After coming in contact with an animal, animal feed, or animal waste

8. After touching pet food or pet treats

9. After handling garbage

Alpha science classroom：How to properly wash your hands for kids?

1. Turn on the Water: Clean, running water is more important than temperature. Turn on the water and get your hands wet. You can turn the water off or leave it running, depending on your preference. Turning it off saves water, but it will increase the number of times you touch the faucet, which will expose you to germs that are on the faucet handles.

2. Lather Up: Soap is important. It helps lift the germs and microbes off your skin while you wash your hands and make the whole process more effective. Studies have shown that it's no better to use antibacterial soap than regular soap, and the overuse of triclosan, a commonly used ingredient in antibacterial soap, could actually contribute to antibiotic resistance.

3. Scrub for at least 20 Seconds: Most people don't scrub their hands nearly long enough. Twenty seconds doesn't sound like a long time but it is much longer than you would imagine. How do you make sure you are washing the proper amount of time? Sing the Happy Birthday song to yourself (or out loud) twice. Make sure you are completely covering your hands with soap and water. Scrub between your fingers, under your nails, all over your thumbs and up your wrists. There are germs all over your hands, not just on your palms and fingertips.

4. Rinse the Soap (and Germs) Away: Rinsing is ultimately how you get the germs off of your hands, so it's really the most important step. Again, it's important to use clean running water. Dipping your hands in a stagnant pool of water (or even standing water in the sink) is not the same as rinsing the soap off with clean, running water. If all you have is a pool of water—for instance, you are outside and have no access to running water—it is better than nothing and certainly preferable to not washing your hands at all. Many people don't realize that washing your hands doesn't typically kill germs, it is simply the most effective way to get them off of your hands so you don't spread them to yourself or others. Rinsing allows you to wash the germs and microbes away, drastically cutting down the chances that you will spread disease.

5. Dry Your Hands: Using a paper or cloth hand towel, dry your hands completely. If you are using cloth hand towels, they should be washed frequently—especially if they are in a shared household where they could become contaminated easily.

6. Turn Off the Water: If you want to save water, go ahead and turn the water off after you get your hands wet and then on and off again when you need to rinse them. According to the CDC, "While some recommendations include using a paper towel to turn off the faucet after hands have been rinsed, this practice leads to increased use of water and paper towels, and there are no studies to show that it improves health." Use your best judgment here. You also might want to consider using your paper towel to open the bathroom door as you're leaving if you're using a public restroom.

In the end, Alpha science toys wash their hands carefully with kids after doing an antimicrobial soap science experiments for kids to ensure our health. Alpha science toys carefully explain a series of scientific knowledge about the type of bacteria, how to grow and where to put the bacteria, through three courses of bacterial growth science experiment for kids, bacterial inhibitor science experiment for kids and antibacterial soap science experiment for kids. In the face of special disasters around the world, Alpha science toys company hopes that every child can protect themselves well, apply the scientific knowledge they have learned to their lives, avoid being threatened by bacteria, and become the healthiest and smartest scientists.