Ninth Grade, Human Biology & Health Science Experiments (Page 11)

Heart Rate Recovery Times

Science Fair Project Idea

Scientific Method

Over an average lifetime, the human heart beats more than 2.5 billion times, supplying blood to the entire body. When a person exercises, the heart has to work harder than usual. Have you ever wondered how quickly your heart beats when you exercise, or how long it takes to recover back to its normal rate after you are done exercising? Is the heart rate recovery time faster for people who get regular exercise compared to people who do not? Try out this science project to find out! Read more

How Can Vaccines Be Used to Fight Outbreaks?

Science Fair Project Idea

Scientific Method

Stopping a viral outbreak like COVID-19 takes more than luck, it takes public health tools. Vaccines are considered to be one of the best public health tools, which is why there is often a rush to develop good vaccines for newly discovered viruses, particularly those that have the potential to infect lots of people. Recent examples include COVID-19, Zika virus, and Ebola. If enough people are vaccinated, an effective vaccine can help stop outbreaks or even eradicate (completely get rid of) a… Read more

How Fast Is Your Reaction Time?

Science Fair Project Idea

Scientific Method

Many sports skills require quick reaction times: think of hitting a 95-mph fastball, returning a 100-mph tennis serve, or blocking a slapshot at the net in hockey. (The Experimental Procedure section below has one way to measure reaction time.) Is your right hand faster than your left? Can you improve your reaction time with practice? Do both hands improve if you only practice with one hand? Try relating your reaction time to real situations in your favorite sport. For example, calculate… Read more

How Protective is Your Helmet?

Science Fair Project Idea

Scientific Method

Every time you hop on your bike or gear up for football or baseball practice, your helmet is your first line of defense. Whether you’re coasting downhill or tackling on the gridiron, impacts happen — and they can cause more than just bumps and bruises. Scientists tell us that forceful hits to the head can lead to concussions or even more serious brain injury over time. Correct helmet design, proper fit, and good cushioning all help reduce those risks. For example, bicycling is one… Read more

How Shoe Tread Affects Traction

Science Fair Project Idea

Scientific Method

Have you ever noticed that some shoes grip the ground better than others? The pattern and design of a shoe’s tread can affect how slippery it is on different surfaces. You can test shoes with different tread patterns—like flat, ridged, or patterned—to see which design provides the best grip. By dragging a shoe along a surface with a spring scale at a constant velocity, you can measure how much force is needed for each shoe to slide on various surfaces. With this knowledge, you… Read more

How Sour or How Sweet is Your Lemonade?

STEM Activity

Cooking is a fun and rewarding activity, allowing you to be cook and a scientist at the same time, experimenting with endless taste combinations! The five tastes humans can experience are: sweet, sour, salty, bitter and umami. But have you ever experienced some combinations that were delicious and others that were downright yucky? How do cooks come up with delicious recipes, and even more amazingly, how can they replicate the same exact flavors over and over again? Does science have anything to… Read more

How to Help Pass Gas

STEM Activity

1

2

3

4

5

1 review

Has your stomach ever ached so bad you felt as if it was blown up like a balloon—maybe after the big Thanksgiving meal? You may have had a large amount of gas trapped in your stomach and intestines. But where does the gas come from that makes you feel so uncomfortable, and how does it disappear again? In this activity, you will blow some bubbles to investigate how a specific medicine can help you feel better, so next time your tummy hurts because you are bloated, you will know how to cure… Read more

How Warm is Just Sweet Enough?

STEM Activity

1

2

3

4

5

3 reviews

Can you recall how a piece of warm apple pie or a cup of hot chocolate milk tastes when you let it cool? Maybe you even prefer to have these treats at room temperature. Why is this? Can flavor change even when you are not adding ingredients, cook or bake it? Try this activity and discover how temperature influences flavor! Read more

I See a Full Moon Rising...and Shrinking...or Do I?

Science Fair Project Idea

Scientific Method

Have you ever noticed how the moon appears bigger at the horizon, just as it is rising over the treetops, than it does later in the evening when it is overhead? Of course, the size of the moon does not change, but our perception of its size changes based on where it is in the sky. In this human biology science fair project, you will investigate Emmert's law, which explains the full moon illusion. You will estimate the size of the perceived increase in the size of the moon at the horizon. Read more

Lung Capacity and Age

Science Fair Project Idea

Scientific Method

Our metabolism changes as we get older, a sad fact of life that we cannot change. Old age affects our bodies in many ways. Changes in musculature, bone strength, energy, diet and breathing are some of the many ways we change as we age. You might notice that people often get out of breath when they are older and doing a physical activity. Why do some people feel out of breath, while others do not? Does this change correlate with age? Could this reflect a difference in lung capacity between… Read more

Ninth Grade, Human Biology & Health Science Experiments (136 results)

Explore Our Science Videos