The musculoskeletal system can feel like a “label-the-diagram” unit if we let it. Students memorize bone names, forget them, and miss the bigger idea: your skeleton and muscles are a living, responsive system that builds, repairs, powers movement, and even supports blood production.

One of my favorite ways to teach this topic is to start with jaw-dropping facts that force students to explain what’s happening. Curiosity first, vocabulary second, and deeper understanding third. That’s exactly why a Strange But True Facts + Two Truths & a Lie format works so well as a lesson opener, review tool, or low-prep sub plan.

If you want a ready-to-go classroom version designed for middle and high school, this is the featured resource that pairs directly with today’s blog post - Musculoskeletal System Strange But True Facts + 2 Truths and a Lie Activity Set

And if you’d like a broader “grab and go” collection of anatomy and physiology resources, this hub makes it easy to browse muscles, bones, tendons, ligaments, body systems, and more - Health and Anatomy Resources.

Now, let’s jump into six facts that reliably get students leaning forward.

A quick teaching playbook: how to use these facts in real classrooms

Before the facts, here are three classroom formats that keep the learning tight and actually manageable:

1) Two Truths & a Lie (10–15 minutes)

Give groups three statements (2 true, 1 false). Students must choose the lie and justify their reasoning. This naturally brings out misconceptions, and it makes every student show their thinking.

2) Micro-CER (8–12 minutes)

Students choose one fact and write a mini Claim–Evidence–Reasoning response:

• Claim: What does this show about bones/muscles?

• Evidence: Quote the key number or detail.

• Reasoning: Explain the biology behind it.

3) Stations (25–35 minutes)

Each station is one fact + a diagram + 2 questions. Students rotate and build a one-page “Musculoskeletal Myth-Buster” sheet.

If you like structured reasoning beyond “fun facts,” this scaffold makes the skeleton unit much more thoughtful and discussion-driven - The Skeleton Critical Thinking Framework Resource.

The 6 Incredible Facts

Fact 1: Bones are piezo-electric

Bones can generate tiny electrical charges when they’re mechanically stressed. In research literature, bone’s piezoelectric behavior is linked to its collagen structure, and these electrical signals are connected to bone remodeling and osteoblast activity. (PMC)

Why students remember this: It flips the idea that bones are dead rods. Bones respond to forces and adapt. That’s why weight-bearing exercise supports bone strength.

Teach it tomorrow (easy):

• Prompt: “If bones respond to stress, what happens when someone is in a cast for weeks?”

• Quick link to real life: astronauts and bone density, sedentary lifestyles, athletics.

Fact 2: Your stapes is smaller than a grain of rice

The stapes is the smallest bone in the human body and is only a few millimeters long. (NCBI)

Why this matters in a musculoskeletal unit: It expands skeleton beyond the obvious. Students tend to think bones only exist in limbs and the skull. This fact makes the skeleton feel whole-body.

Teach it tomorrow (easy):

• Ask: “Why would a tiny bone be useful in hearing?”

• Extension: “What happens if that tiny structure becomes fixed or damaged?”

Fact 3: Weight-for-weight, a femur outperforms concrete and rivals steel

Bone is remarkably strong for its weight. A commonly cited comparison notes that a cubic inch of bone can, in principle, bear extremely large loads, and bone can be stronger than concrete by weight. (Live Science)

Important classroom nuance: Strength depends on how force is applied, direction of load, and rate of impact. So you can teach the headline fact while also teaching scientific precision.

Teach it tomorrow (easy):

• Engineering prompt: “How can something be strong and still break in a sports injury?”

• Mini-model: compare compression vs bending vs torsion with simple materials (straws, sticks, foam).

Fact 4: The hyoid is a “floating” bone

The hyoid bone is unusual because it does not directly articulate with other bones. It’s suspended by muscles, ligaments, and soft tissues, supporting swallowing and speech. (Cleveland Clinic)

Why students love this one: It sounds impossible. A floating bone instantly triggers questions about structure and function.

Teach it tomorrow (easy):

• Ask: “If it doesn’t connect to other bones, why doesn’t it just drift?”

• Link to function: swallowing, tongue movement, airway.

Fact 5: Bone marrow makes about two million red blood cells every second

Your skeleton is a blood-cell factory. Multiple reputable sources describe red blood cell production in the millions per second range, produced in the bone marrow. (NCBI)

Why this is a big deal for learning:It connects the musculoskeletal system to the circulatory system and makes “body systems” feel interconnected, not siloed.

Teach it tomorrow (easy):

• Ask: “Why would the body place blood production inside bones?”

• Extension: “What happens if bone marrow is damaged?”

A great companion reading for this systems-connection is a blood types passage that’s designed as a quick science literacy task - Blood Types Reading Passage with Questions

Fact 6: The diaphragm flexes around 20,000 times per day

We take about 20,000 breaths per day on average, meaning the diaphragm is doing an incredible amount of repetitive muscular work. (Mayo Clinic Health System)

Why it belongs in a musculoskeletal unit: Students often separate “muscles” from “breathing.” This fact connects muscles to respiration, posture, and movement.

Teach it tomorrow (easy):

• Ask: “If the diaphragm is a muscle, how is it different from your biceps?”

• Quick tie-in: why breathing patterns can affect posture and performance.

A simple 3-lesson sequence that feels modern (and stays doable)

Here’s a tidy sequence you can run across Grades 6–10:

Lesson 1: Curiosity and misconceptions

• Start with 2 Truths & a Lie using musculoskeletal facts.

• Students justify answers using vocabulary (bone marrow, osteoblast, diaphragm, articulation).

• Exit ticket: “One fact I didn’t believe at first, and what changed my mind.”

Resource that supports this instantly - Musculoskeletal System Strange But True Facts + 2 Truths and a Lie Activity Set

Lesson 2: Science literacy and systems thinking

• Students read a short passage (muscles, bones, tendons, ligaments).

• Add one graph or data point (bone density vs age, injury rates, etc.).

• Micro-CER: “Explain how structure supports function in one part of the system.”

Browse the A&P collection for quick text-based builds like muscles, bones, tendons and ligaments - Health and Anatomy Resources.

Lesson 3: Make thinking visible

• Students use a structured thinking scaffold to go beyond naming parts.

• Discussion: “What daily habits strengthen or weaken this system, and why?”

• Assessment option: one-page “Myth-buster” poster using evidence.

A ready scaffold for this style of lesson - The Skeleton Critical Thinking Framework Resource

Why this approach works (without feeling gimmicky)

Facts like these are not fluff. They are attention anchors. Students remember the surprising hook, then you attach the real science: cells, tissues, biomechanics, homeostasis, and systems interactions.

And because the activities are flexible (digital, print, whole class, stations, sub plan), you can use them as:

• a unit opener

• a review day that still has rigor

• a fast formative assessment

• a “lesson filler” that actually teaches something

If you want a wider set of body systems resources in the same style, this is a good browse point - Human body systems strange but true facts + 2 truths and a lie resource.

Thanks for reading

Cheers and stay curious

Oliver - The Teaching Astrophysicist