Urinary System Functions Lesson Plan (TEKS 7.13A): A Complete 5E Lesson for the Kidneys, Nephrons, and How the Body Filters Blood

Chris Kesler · 10 min read

The first time I taught the urinary system to a class of 7th graders, the snickering started about three seconds in. Anything involving pee is hilarious to a 12-year-old. Once I got past the initial wave of giggles and asked the actual question ("What does pee come from?") the answers were not great. "Your stomach." "Water you drink." "The bladder makes it." Nobody mentioned the kidneys. Nobody mentioned the blood. Nobody mentioned the fact that the entire reason you pee is to get rid of toxic waste before it builds up.

What flipped it was the day I held up a coffee filter and a pitcher of dirty water. I poured the water through the filter, showed them the dirt left behind in the filter and the cleaner water that came through, and said "this is your kidneys, every minute of your life, filtering your blood." Then I told them the kidneys process about 50 gallons of blood a day to produce a quart of urine. The giggles stopped. Suddenly the urinary system wasn't a body system you joke about. It was a 24/7 water-treatment plant nobody had ever told them about.

That's the core idea behind this 5E lesson for TEKS 7.13A. Students don't just memorize "bladder holds pee." They explore how the kidneys filter blood, why hydration matters, and how the urinary system keeps the entire body in chemical balance.

⏱ About 10 class periods 📓 7th Grade Life Science 💧 TEKS 7.13A 🎯 Differentiated for D + M 💻 Print or Digital

Inside the Urinary System Functions 5E Lesson

The 5E instructional model walks students through five phases: Engage, Explore, Explain, Elaborate, and Evaluate. It flips the traditional lecture-first sequence on its head. Students explore a concept hands-on before you ever explain it, which means by the time you do explain it, they have something to hook the vocabulary onto.

I switched to the 5E model years ago and stopped going back. Kids retain more, ask better questions, and stop staring at me waiting to be told the answer. The Urinary System Functions 5E Lesson is built on this framework from start to finish. Here's how it plays out across the five phases.

🎯 Engage

I CAN statement and key vocabulary for the urinary system functions lesson

Day one is a teacher-led hands-on exploration. Each small group gets a coffee filter, a cup of "blood" (water mixed with sand, glitter, and food coloring representing waste), and an empty collection cup. Following the teacher directions, they pour the "blood" through the filter and observe what passes through versus what gets caught. Each group also gets a body diagram and a set of four urinary organ cards (kidneys, ureters, bladder, urethra) and arranges them in order along the path of urine.

By the end of the period, kids have the urinary tract diagrammed, an annotated student sheet showing the filtering process, and they can explain in their own words why the kidneys are doing the actual work and the bladder is just storage. Nobody has heard a vocabulary lecture yet. That's the point. They walk into the rest of the unit with a working model of filtration, not a memorized list of organs.

What's included in the Engage:

Teacher directions for the kidney-filtration activity
Printable student observation sheet
Answer key for the discussion questions
Four learning objective slides (standard verbatim, "Describe" verb highlighted, "I CAN...", and "WE WILL...")
An illustrated Body Systems Word Wall in English and Spanish covering the full unit vocabulary

🔬 Explore

📷 Explore image 1 — wide shot of Station Lab in action

The Urinary System Functions Station Lab is the heart of the Explore phase. Students rotate through 8 stations (plus a 9th challenge station for early finishers) over one class period. The Station Lab is split into four input stations (where kids take in new information) and four output stations (where they show what they learned).

The four input stations:

🎬 Watch It! — Students watch a short video on the structure and function of the urinary system and answer guided questions about the kidneys, nephrons, and the path of urine.
📖 Read It! — A one-page reading passage at two differentiated levels, with a Spanish version included.
🔬 Explore It! — Students build a kidney filtration model using sand, gravel, and a coffee filter inside a clear cup to simulate the filtering process of a nephron.
💻 Research It! — Reference cards on the four main parts of the urinary system, the nephron (the kidney's filtering unit), what gets filtered out of blood, and the role of accessory organs (liver, lungs, skin) in waste removal.

The four output stations:

📋 Organize It! — A card sort where students place substances (water, urea, salts, sugar, oxygen, blood cells) under "filtered out and excreted" or "kept in the blood" and justify each choice.
🎨 Illustrate It! — Students draw a labeled diagram of the urinary system showing the kidneys, ureters, bladder, and urethra, and trace the path of urine from blood filtration to exit.
✍️ Write It! — Three open-ended questions in complete sentences (this is where you see who really understands homeostasis and hydration).
📝 Assess It! — A short formative check with multiple choice and a fill-in-the-blank vocabulary paragraph.

📷 Explore image 2 — close-up of featured station (Explore It! or Organize It!)

Print and digital versions are both included. If you want the full breakdown of what happens at every single station, what students produce, and how to set it up, that's in our dedicated Station Lab post.

→ Read the full Urinary System Functions Station Lab walkthrough 8 stations, materials list, teacher tips

The Station Lab is included in the full 5E lesson. You don't need to buy it separately if you're getting the whole unit.

📚 Explain

📷 Explain image 1 — Presentation slide screenshot

Here's the real payoff of doing the Engage and Explore before the Explain: by the time kids hit this phase, they've already filtered "dirty blood" through a coffee filter and ordered the urinary organs on a body diagram. They have a working understanding before you ever start naming things. The discussions get deeper, the questions get sharper, and you spend less time defining and more time pushing their thinking.

The Urinary System Functions Presentation walks 7th graders through the full scope of TEKS 7.13A for this system, one concept at a time. The deck opens with the big function of the urinary system: it filters blood and removes liquid waste from the body. The deck also frames the urinary system as a key partner in homeostasis, the body's effort to maintain stable internal conditions. The urinary system works with the circulatory, respiratory, endocrine, and integumentary systems to balance water, ions, pH, blood pressure, calcium, and red blood cells. It's not just about pee. It's about keeping the entire body chemically stable, every minute, around the clock.

📷 Explain image (middle) — Presentation slide screenshot (classification hierarchy, Essential Question, or category comparison)

From there the deck walks through the four main organs of the urinary system in order. The kidneys are two bean-shaped organs about the size of a fist, sitting just below the rib cage on either side of the spine. They're the actual filters of the system. Blood enters each kidney through the renal artery and exits cleaner through the renal vein. Inside each kidney are about a million tiny filtering units called nephrons. Each nephron pulls water, salts, urea, and other small molecules out of the blood, then carefully returns most of the water and useful substances back, while letting the actual waste continue on as urine. The kidneys process about 50 gallons of blood every day to make about a quart of urine. From the kidneys, urine flows down two muscular tubes called the ureters, which are about 10 to 12 inches long, into the bladder. The bladder is a pear-shaped muscular sac that stores urine until you're ready to release it. An average bladder holds 400 to 600 milliliters (about two cups). When it fills up, stretch receptors signal the brain that it's time. Finally, urine exits the body through the urethra.

Then the lesson tackles the chemistry of filtering, which is what really separates the urinary system from "the system that pees." The kidneys remove urea, a nitrogen-based waste produced when cells break down proteins. They balance water, holding more when you're dehydrated and releasing more when you're over-hydrated. They balance salts and electrolytes like sodium, potassium, and calcium, which the muscular and nervous systems need at very specific concentrations to function properly. They also help regulate blood pressure by adjusting how much fluid stays in the blood. The deck includes a built-in matching activity where students drag substances to "filtered out" or "kept in." Once kids see what the kidneys are actually deciding minute-by-minute, the system clicks.

📷 Explain image 2 — Presentation slide screenshot

The deck also covers hydration, which is the single most useful real-world takeaway for a 7th grader. Water makes up about half your body weight. You lose water every time you breathe, sweat, and pee. If you don't replace it, you become dehydrated, and the symptoms (dark urine, fatigue, thirst, headache, dizziness) all show up because the kidneys are working overtime to conserve water. The deck connects this back to the cross-system thinking of TEKS 7.13A. The urinary system works closely with the circulatory system (blood is what gets filtered), the endocrine system (hormones like ADH tell the kidneys how much water to keep), the respiratory system (lungs remove CO₂ waste while kidneys remove urea waste), and the integumentary system (skin removes some waste through sweat).

What makes the Urinary System Functions Presentation different from a typical body-systems slideshow is that kids are doing something on almost every slide. It's not a lecture deck. It's a participation deck. "Your answer:" prompts appear on most slides, Brain Breaks reset attention every few slides (one walks kids through creating a mnemonic for the four organs of the urinary system), and Quick Action INB tasks (organ labeling, accessory organ sorting, filter content matching) show up throughout. Think About It prompts push deeper into bigger ideas like how lifestyle and hydration affect kidney health and how a 3-D model of the system would actually work. The deck closes with a Check for Understanding tied back to the Essential Questions: What is the main function of the urinary system? and How does it interact with the other body systems?

The Explain materials in this product include:

An editable Presentation at two differentiated levels (Dependent and Modified), works in PowerPoint or Google Slides
A guided fill-in-the-blank student notes handout that mirrors the Presentation, with answer key
A Paper Interactive Notebook (English and Spanish) students cut, fold, and glue into their notebooks
A Digital Interactive Notebook at both levels with answer keys, for 1:1 classrooms or Google Classroom

The Explain runs across two class periods. The built-in Think About It prompts are where the real discussion happens, so let those breathe.

🛠️ Elaborate

Student choice project options and rubric for the urinary system functions lesson

The Elaborate phase is where students stretch what they learned about the urinary system and put it into a project of their choosing. In this 7th grade life science lesson, that's a Student Choice Project board with six different project options plus a "design your own" pathway.

Students might build a 3-D model of the kidney showing how a nephron filters blood, design an infographic explaining the importance of hydration and how to spot dehydration, write a short story from the point of view of a drop of water as it travels from a glass of lemonade into the kidneys and out as urine, or record a video walking through what happens to the urinary system during a hot summer day of soccer practice. There are options for kids who love to write, kids who love to draw, kids who love to build, and kids who love to perform. Whatever the project, the point is the same: students apply kidneys, nephrons, the path of urine, and homeostasis to a real-world artifact instead of a worksheet.

Choice is the whole point. By letting students pick how they show their thinking, you get more authentic work for TEKS 7.13A and you actually get to see what they understand about the urinary system.

The rubric (the part teachers actually want)

Every project, no matter which option a student picks, is graded on the same rubric. Five categories at 20 points each:

Vocabulary (20 pts) — At least four words from the lesson are used in context.
Concepts (20 pts) — At least two key concepts from the lesson are referenced.
Presentation (20 pts) — The project grabs attention and is well-organized.
Clarity (20 pts) — Easy to understand. Free of typos.
Accuracy (20 pts) — Drawings and models are accurate. The science is right.

The rubric uses a minus / check / plus shorthand on every row so you can grade a stack of projects quickly without re-reading every criterion.

Two differentiated versions in one file

The standard version is for students ready for independent application of urinary system ideas. The Reinforcement version is for students who need additional vocabulary or concept support. Three of the six options are swapped for projects with a tighter vocabulary tie-in, and "design your own" is replaced with "collaborate with the teacher" so kids aren't pitching cold.

✅ Evaluate

The Evaluate phase wraps the unit with a formal assessment. It's not all bubble-in. Several questions show students labeled diagrams and ask them to identify the organ, explain what gets filtered, or describe the role of the urinary system in homeostasis.

The full assessment has 12 questions across five formats:

Multiple choice (4 questions) covering the four main organs of the urinary system, the function of the nephron, what gets filtered out of blood, and how the urinary system maintains homeostasis
Hotspot / visual (2 questions) where students click the kidneys on a body diagram and identify the structure that carries urine from the kidney to the bladder
Multiselect (2 questions) where students pick all of the substances that the kidneys filter out, and all of the systems that the urinary system interacts with
Short answer (2 questions) on how the kidneys filter blood and on how the urinary system helps maintain homeostasis through water balance
Multipart scenario (2 questions) with a real-world example (a student playing soccer in the heat without drinking water) where students explain what happens to urine color, how the kidneys conserve water, and what other systems are affected

A modified version is included for students who need additional support. Fewer multiple-choice distractors and sentence-starter scaffolds on the short-answer items.

If you've taught all five phases, this assessment shouldn't surprise anyone. It's a chance for kids to show you they get it.

How everything fits together

If you want the whole experience (Engage hook, the Station Lab as the Explore, the Explain day with Presentation and interactive notebook, the Student Choice Elaborate, and the Evaluate assessment all in one download), that's the Urinary System Functions Complete 5E Science Lesson.

If you only need the one-day hands-on activity, the Station Lab works as a standalone. Most teachers buy the full 5E because the Station Lab works harder when it's bookended by a strong Engage and a follow-up Explain. But both are honest options.

Two options

Urinary System Functions Complete 5E Lesson cover

Full 5E Lesson — ~10 class periods $13.20 Get the 5E Lesson

Urinary System Functions Station Lab cover

Just the Station Lab — 1–2 class periods $7.20 Get the Station Lab

What you need to teach Urinary System Functions (TEKS 7.13A)

Materials beyond what's in the download:

Coffee filters, clear cups, sand, gravel, glitter, and food coloring for the Engage filtration activity and the Explore It! kidney model
Printed urinary organ cards and body diagrams for the Engage activity (templates included)
Index cards for the "filtered out vs. kept in" sort at the Organize It! station
Pencils, colored pencils or markers, and printed student pages
A device with internet for the Watch It! station and the slide deck

Standard covered: Texas TEKS 7.13A — Describe the function and interactions of major body systems in organisms, including the skeletal, muscular, nervous, respiratory, integumentary, circulatory, endocrine, digestive, immune, and urinary systems. See the full standard breakdown →

Grade level: 7th grade science

Time: About 10 class periods of 45 minutes each, done with fidelity. The product also ships with a compressed sample unit plan if you need to move faster.

Common misconceptions this lesson clears up

"The bladder is what filters the blood"
The bladder doesn't filter anything. The bladder is a storage tank. It's a stretchy muscular pouch that holds urine until you're ready to go to the bathroom. The actual filtering happens in the kidneys, which sit higher up in the body, just below the rib cage. Inside each kidney are about a million tiny filtering units called nephrons that pull waste out of the blood and turn it into urine. The urine then travels down the ureters to the bladder for storage. So the order is: kidneys filter, ureters transport, bladder stores, urethra releases. The bladder gets all the attention because it's the part you actually feel, but the science work happens in the kidneys.
"If you drink a glass of water, you pee that exact water out almost immediately"
It feels like that sometimes, but it's not what's happening. When you drink water, it's absorbed through the walls of your small intestine into the bloodstream. From there it joins the rest of your body's water and gets distributed everywhere your blood goes. The kidneys then make tiny adjustments minute-by-minute: if you have plenty of water, they let more out as urine. If you don't, they conserve and pull water back into the blood. The urine you produce after drinking water is mostly water that was already cycling through your body, not the exact molecules you just swallowed. Hydration is a balance, not a one-way pipe from mouth to bathroom.
"Yellow urine means something is wrong with you"
Yellow urine usually doesn't mean you're sick. It mostly means you're not drinking enough water. The color of urine comes from a pigment called urochrome, which is always there. When you're well hydrated, your urine is diluted with extra water and looks pale yellow or nearly clear. When you're dehydrated, the kidneys conserve water by making more concentrated urine, and that same pigment looks much darker yellow. A quick check before you decide anything is wrong: look at the color, then drink a couple glasses of water and check again an hour later. If the color lightens up, the issue was hydration. If urine stays dark for days or has other weird changes (red, brown, cloudy), that's when it's time to mention it to an adult. Color is mostly a hydration meter, not a sickness alarm.
"You can't live without both kidneys"
Most people are born with two kidneys, but you only actually need one to survive. People who donate a kidney to a family member, or who lose one to disease or injury, go on to live full and healthy lives with just one remaining. The remaining kidney often gets a little bigger over time and does the work of both. Some people are even born with only one kidney and never realize it until a doctor finds out by accident. Two kidneys is the backup design. One kidney is enough. (Which makes the misconception especially worth fixing, because some kids assume losing a kidney is a death sentence when it's actually a survivable situation that millions of people live with.)

What's included in the Urinary System Functions 5E Lesson download

📷 Inside-the-product — add screenshot of Read It passage or sample answer sheet

When you buy the Urinary System Functions Complete 5E Lesson, you get a single download with the whole unit:

✅ Engage materials — teacher directions, student observation sheet, answer key, four learning objective slides, illustrated Body Systems Word Wall (English + Spanish)
✅ The full Station Lab — 8 stations + 1 challenge, print and digital, two reading levels, Spanish Read It!
✅ Explain materials — editable Presentation at two differentiated levels (with built-in Brain Breaks, Quick Action INB tasks, and Think About It prompts), guided fill-in-the-blank student notes handout with answer key, Paper Interactive Notebook (English + Spanish), Digital Interactive Notebook at two levels with answer keys
✅ Elaborate (Student Choice Projects) — 6 project options + design-your-own, plus a Reinforcement version with vocabulary-focused alternatives, 5-category rubric included
✅ Summative assessment — full 12-question version and modified version with sentence-starter scaffolds, both with answer keys
✅ Sample unit plan — day-by-day pacing guide

A couple of real-talk tips from running this lesson

1. Lead with the coffee filter demo on Day 1.

Before any vocabulary at all, pour dirty water through a coffee filter in front of the class. Show them the dirt left behind and the cleaner water that comes through. Then say "this is your kidneys, every minute, all day." That single 60-second demo reframes the entire unit. The urinary system goes from "the system that pees" to "the system that filters."

2. Use the 50-gallons-a-day stat early.

Your kidneys filter about 50 gallons of blood every single day to produce about a quart of urine. That ratio (50 gallons in, 1 quart out) tells the whole story of how selective the system is. 7th graders find that stat genuinely shocking. Use it on Day 1 and again on the assessment review.

3. Walk kids through urine-color self-checks.

The hydration conversation lands better when it gets practical. Show them the urine color chart (pale yellow = good, dark yellow = drink water, almost clear = also fine). It turns the whole unit into something they can actually use that afternoon. Side benefit: it gives the giggles somewhere productive to go.

Get the Urinary System Functions 5E Lesson

Buy the full Urinary System Functions 5E Lesson — $13.20

Or if you only need the one-day hands-on Station Lab:

Buy the Urinary System Functions Station Lab — $7.20

(The Station Lab is included in the full 5E Lesson)

Frequently asked questions

Does this cover all of TEKS 7.13A?

For the urinary system, yes. The full standard asks students to describe the function and interactions of all 10 major body systems. This lesson covers the urinary system in depth, including the kidneys, nephrons, the path of urine, hydration, and how it interacts with the circulatory, endocrine, respiratory, and integumentary systems. We have nine more 5E lessons for the other body systems under the same standard.

What do my students need to know before this lesson?

A basic understanding of cells, tissues, and organs from earlier grade-level standards. If your kids can describe what an organ is and the difference between a cell and a tissue, they're ready. Some prior exposure to the circulatory system also helps but isn't required.

How long does it take to teach?

Done with fidelity, about 10 class periods of 45 minutes each: one day for the Engage, two days for the Station Lab, two days for the Presentation and Interactive Notebook, three days for the Student Choice Project, and one to two days for review and the assessment. A compressed sample plan is included in the file if you need to move faster.

Do I need special supplies?

Just coffee filters, clear cups, sand, gravel, and food coloring for the Engage and Explore It! kidney model, plus printed cards for the organ-ordering activity. Most teachers already have what they need.

Does this work for digital classrooms?

Yes. Every component has a digital version. The Station Lab is fully digital-ready (Google Slides), the Presentation works in Google Slides, and the Student Choice Projects can be submitted as videos, slide decks, or written work.

Is this 5E lesson aligned to NGSS too?

It aligns with MS-LS1-3 (using arguments supported by evidence for how the body is a system of interacting subsystems composed of groups of cells). Built TEKS-first, but the standards overlap.