Unlike science in middle school, high school biology is a hands-on endeavor. Experiments are a standard part of biology courses, whether they are part of a controlled laboratory class, science fair, or individual student projects. Explore a few fascinating high school biology experiments; and discover ideas for simple and easy biology experiments to incorporate into your curriculum.
Examples of Biology Experiments for High School
Whether you are looking for a science fair project or need to create a project for a class assignment, there are numerous biology projects for teens.
Dissecting a frog is a quintessential part of high school biology. If possible, try to get both female and male specimens for your class so students can see the eggs and compare the insides to the male frog.
High schoolers can get a bit squirmy about frog dissection. Have a flower dissection instead. The teens can find and label the female and male parts of the flower. It can be fun for high schoolers to check out flower intricacies under a microscope.
Diversity Among Plant Samples
Another simple biology experiment involves going into your natural environment, such as a local park, to observe diversity among plant samples. To make the experiment more detailed, students can rub collected samples on filter paper to observe which plants present which colors. Teens can work to find out why certain plants present certain colors.
It can be enlightening to show kids how phototropism affects plants. They can set up an experiment by using different materials to affect light. They can see how affecting the light affects the growth of the plant.
Water From Common Sources
Water is everywhere. Unfortunately, water contains numerous elements too. A great experiment is collecting water samples from various sources and viewing them under a microscope. Students can then compare their results and attempt to postulate why a given water source would present more organisms than another would.
Another experiment involves taking a piece of bread to monitor the molds that grow over a period of two weeks.
Everyone has their own taste. Literally! Some people like sour things while others like sweet. Find out if everyone perceives taste the same way and has the same threshold for taste by doing an in-class experiment.
Ever wonder how effective hand sanitizer is at killing bacteria? Test it! Grow bacteria in a Petri dish along with paper soaked in peroxide, white vinegar, rubbing alcohol, etc. Find out how each one of them works to inhibit bacteria growth.
Pea Plant Genetics
Students can recreate Mendel's genetic pea plant experiments. By growing pea plants and comparing their phenotypes, students can determine each parent plant's genotype.
Fingerprints are pretty amazing features on the human body. Not only can you use them to open your phone, but each one is unique. Put your fingerprint on paper and examine the different aspects of the lines and arches on your fingers. Compare fingerprints among everyone in class.
Comparing Animal and Plant Cells
To better understand animal and plant cells, students can compare cells from their cheeks to cells from an onion. Just stain the cells with iodine or another dye to better see the cell structures under a microscope.
Creating a DNA model is a great way to help students understand the structure and function of DNA in genetics. Students can use candy, string, and toothpicks to develop a fairly realistic model of the double helix structure.
Water Bottle Germs
Many people refill their water bottles in high school. But do they add germs or bacteria to the bottle? Is refilling a disposable water bottle safe? Have students take swabs of the water bottles they use and look for bacteria around the lid or on the bottle.
Teens use a lot of hair products. But do they truly work? Have teens in your class take a few samples of their hair. See what happens to the hair when common hair products are added.
Understanding the water cycle isn't hard. But teens can look at it firsthand by creating a water cycle experiment. Just have them fill a baggie with water and tape it to a window. They will watch evaporation, condensation, and precipitation in action.
Closed Ecosystem Bottle
It can be hard for students to imagine something having its own ecosystem. However, you can use a plastic bottle to create a closed ecosystem.
Field Survey Biology Experiment
This experiment is great because it is cheap, easy, and you can do it in a variety of areas around your school or send students home with it. The goal is to observe the surrounding area over time and monitor the samples that you collect.
Materials You'll Need
For this experiment, you need to grab:
- Jar or baggies to collect samples
- Stakes and string or cones help mark an area
- Paper or journals for taking notes
- Slides, slide covers, and a microscope
Take note that you will observe your area for several months, so choose an area that is easy to re-mark or where you can leave the markings up, so you return to the same designated area each time.
- Have students choose one spot to observe. The spot should be no more than two to three feet square.
- They should write down and notice everything they see. Examples of guiding questions include:
- Do you see evidence of animals? (Look for prints, scat or guano, fur, owl pellets, etc.)
- What plant life do you see? (Look for moss, lichen, weeds, and other plants).
- What fungus do you see? (Look for mushrooms and other fungal growth).
- What insects do you see? (Encourage students to look specifically for relationships here - such as connecting mosquitos with water or bees with flowers or a hive).
Sampling and Classroom Instructions
Bring the research back into the classroom by following these instructions.
- Guide students to make connections and note relationships in their marked area. Have them inventory the area and draw a crude map of where everything is.
- If possible, have students use tweezers and gently take samples of soil, fungus, moss, plant life, insects, etc.
- Back in the classroom, study the samples. Things you can look for include:
- pH value of soil or water
- Microorganisms in water
- Plant cells under a microscope
- Comparative structure of flowers you find
- Require students to record everything in their own journal or interactive notebook.
Teacher tip: Set up stations in the classroom for viewing, dissecting, drawing, testing pH, etc. This will allow students some choice in how they proceed with examining their specimens.
Testing for Bacteria
Have students see where the most bacteria are lurking. This experiment is great if you want a lab that has guaranteed results. There is always some kind of bacteria lurking somewhere, just waiting to grow in a student's Petri dish.
These are the materials you are going to need to have on hand.
- Prepared Petri dishes, three per student
- Sterile swabs
- Painter's tape
- Scotch tape
- Permanent Marker
- Graph paper
Material notes: You can also purchase sterile Petri dishes and agar separately; however, it is much more likely students will contaminate the plate before they swab.
Preparing Your Petri Dishes
Prepping your Petri dishes is an essential part of the experiment.
- Before opening any materials, have students identify three places (but in one physical location such as at home or at school) that they are going to swab for bacteria. Encourage them to hypothesize about which place they think will grow the most bacteria.
- Using the Petri dish, trace three circles on the graph paper and cut it out.
- In pencil, draw a line to denote the 'top' of the circle. It doesn't matter where you draw the line, but you will need something to show you how your Petri dish is oriented so you can be sure you're tracking the same colony each time you observe.
- On the back of the graph paper circle, note the location where you will take the swab, as well as the date you are taking the swabs. Do this for all three Petri dishes you have.
Have students bring their unopened sterile swabs and closed Petri dishes to the site. Carefully, they should:
- Set the Petri dish down on a flat surface.
- Unwrap the swab.
- Swipe the swab across the area they suspect has bacteria.
- Lift the lid, gently wipe the used swab across the agar, and close the lid, carefully but quickly.
Hint: Sometimes, it's helpful to tape the Petri dish shut so that the Petri dish doesn't accidentally lose its lid.
Now that you've swabbed the areas, it's all about the results.
- Have students draw Petri-dish-sized circles in their lab books or on separate graph paper. Draw one week's worth of Petri dishes for each dish the student has.
- As the colonies start to grow, have students draw the size in their notebooks, making daily observations. If they cannot observe daily, have them observe on the same day(s) over a month.
- They should also be recording the color and other notable features of their bacteria colonies in their lab books.
- At the end, the students should write a conclusion of their study.
The Effect of Light on Growth
In this lab, students investigate how light affects plant growth. Students may use any plants, but cress will grow more quickly, so your students can get results faster.
Gather up your materials.
- Styrofoam cup or bowl
- Potting soil
With your materials at the ready, it's time to start your experiment.
- On Day 1 - plant seeds in the soil in the cups.
- Label the cups according to the light you're going to use. You can compare sunlight vs. complete darkness, or you can compare several types of light.
- On each day after the initial day, take a picture of each cup and try to measure the growth, if any.
- For your lab entries, measure the sprouts, and note color and shape characteristics.
In this lab, students watch the rate at which planaria regenerates and test whether how you cut the planaria makes a difference as to how they grow back.
To conduct this experiment, you want to grab.
- 9 planarias
- 3 small plastic Petri dishes
- 1 large plastic Petri dish
- 1 plastic pipet
- 1 magnifying glass
- 1 plastic coverslip
- Spring water
- Permanent Marker
- Paper towels
- Ice pack(optional)
Getting the setup right is half the battle when it comes to creating fun and interesting biology experiments for high schoolers.
- Start by numbering the three small Petri dishes to ensure nothing gets confused later.
- Using the pipet, move a planarian into the large Petri dish.
- At this point, you may want to try to set the Petri dish on an ice pack for a few minutes. This isn't totally necessary, but it will slow the planarian down to make it easier to cut.
- Make three cuts to the planarian:
- Right behind the head
- Right in the middle
- Right towards the tail
- Use the pipet to gently transfer each segment to a new Petri dish (with spring water).
- Repeat the steps with all remaining worm segments.
- Every day, observe the planaria. Regeneration will be considered 'complete' when the photoreceptors (the black dots that look like eyes on the planarian's head) appear.
Scientific Method and High School Biology Experiments
Much of high school biology is focused on instilling the elements of science in students. The scientific method is one of these main focuses. The method prompts participants in science to be investigators and to come up with a guess about what will happen in a given experiment, called a hypothesis. The point of the experiment is then to either prove the hypothesis correct through the experiment or prove it incorrect. This prompts teens to get involved in the scientific method while teaching other scientific skills, such as:
- The ability to make a rational estimate based on present factors and knowledge
- Close detail and monitoring skills
- The possibility of being wrong and how to move past that if it turns out to be the case
- Quick thinking skills
As much fun as biology experiments can be, there is an educational component spearheading the experiment.
Fun and Interesting High School Biology Experiments
For teens, high school biology can be fun. Finding the right experiment can help biology pop off the page and become more than just another required course of study. Who knows? Perhaps your student will even be prompted to enter a science fair or a career rooted in science?