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Why do your biceps bulge?
Human Machine Unit | Lesson 1 of 4

Why do your biceps bulge?

Human Machine Unit | Lesson 1 of 4
Lesson narration:
Scroll for prep

DISCUSS:

What do you think is going on inside your hands when you’re moving your fingers? Any ideas?

DISCUSS:

Take a few moments to move the different parts of your body, and see if you can find all your joints.

DISCUSS:

What do you think would actually be pulling on the strings?

DISCUSS:

Describe how you might go about creating a robot hand that works just like yours.

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skeleton


1 of 12

all of the bones of an animal, including humans
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bones


2 of 12

the hard parts inside many animals that help give their bodies shape

joint


3 of 12

a part of the body where two bones come together and can bend

muscle


4 of 12

a part of the body that attaches to bones and allows the body to move
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bicep


5 of 12

a large muscle in the upper arm

tendon


6 of 12

a part of the body that attaches muscle to bone

function


7 of 12

what something does

system


8 of 12

a group of things that affect each other and function as a whole
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structure


9 of 12

the specific form and shape of something
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dissect


10 of 12

to take something apart to study it
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model


11 of 12

a pretend version of something that scientists use when the real thing is too big, small, or complicated to work with
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observe


12 of 12

to pay close attention to something
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Discussion & Video

The robot hand can't do everything your hand can do.

Ask your student to experiment and figure out what their fingers and hands can do that the robot fingers and hands can't. Ask them: If you wanted to make the robot hand more like your hand, what would you need to add to the robot hand?

Discuss this question as a class. After your discussion, watch the video on the next slide to hear some of the differences the Mystery Science team noticed.

Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Exploration
futuristic Android by Humanrobo , used under CC BY-SA
orange robot by Alexander Kozusev , used under CC BY
roomba stuck in chair by Geekzine Mexico , used under CC BY-SA
Atlas complex futuristic robot by Defense Advanced Research Projects Agency
DARPA falling over by blue hippo films
Atlas robot by Boston Dynamics
firefighter and rescued child by SanchaiRat
girl lunging by axelle b
baby steps by Berenice Garcia , used under CC BY-SA
man running up hill by Alisha Vargas , used under CC BY-SA
Toronto Blue Jays starting pitcher Ricky Romero by Keith Allison , used under CC BY-SA
Portola Palace Stairs by Bernt Rostad , used under CC BY-SA
child riding a bike by Jerry , used under CC BY-SA
Sydney Gonzalez Gymnast by Ruben Gonzales
white android by Hairygael , used under CC BY-SA
duracell batteries by Anton Fomkin , used under CC BY-SA
sandwich by Seph Swain , used under CC BY-SA
Integrated Circuit by Tomasz Mikołajczyk
brain by Sanandros , used under CC BY-SA
brain and nerves by KRITRIM VAULT , used under CC BY
human hand by Johnny Magnusson
robot hand by Peter Ohlmus
human hand bones by OpenStax College
human skeleton by Scott Anselmo , used under CC BY-SA
seattle building by Seattle Municipal Archives
building skeleton by Les Chatfield , used under CC BY-SA
hand x-ray by Noah Weiss
arduino hand robot by Peter Ohlmus
fried chicken by Evan-Amos
white hen by Agricultural Research Service
white king salmon fillet by Isaac Wedin , used under CC BY-SA
Strip Steak by Ɱ , used under CC BY-SA
Activity
rock em sock em by DJ , used under CC BY-SA
Other
Unit: Bicep by daniel64

Featured Reviews

“Making the hand. A couple of the students went home to try to make a robotic arm. Overheard some students say it was the best lesson this year. Of course, I am not surprised to hear cause someone makes this comment most every week. Good to see how excited the students get with Mystery Science lessons for grades 3-4.”
“Making the fingers was very fun for the students. It was hard at times and required a lot of assistance when I wanted to be taking pictures, but in the end it was worth it because they all turned out great and the kids were very proud and excited to show them off to other classrooms in the building and their parents. ”
“My son loved making the robot hand. I enjoyed it as well. It really helped him understand the body mechanics of how muscles, bones and tendons make the hand grasp. He had a great time trying to pick up various objects with it. Best part is that I had all of the materials already in the house for this project. We love Mystery Science!”
“Kids loved building the robot finger. The chicken foot video was AMAZING! I don't think I have ever seen so many "ah ha!" moments than from this lesson. EVERYBODY participated in building the finger. My favorite lesson on here for fourth grade so far. (This is my first year going through the lessons)”
“The video animation that showed the muscle contracting and then showed the ligament connecting the muscle to the bone to make the joint move was a real "a-ha!" moment in the class. You could see the lightbulbs go on. They really enjoyed making and playing with their robotic fingers. I printed the activity onto card rather than paper. We didn't use a separate 3x5 card for the 2cm strip as there was plenty of card left from the print out to use and reduced waste.”
“The videos focusing on key vocabulary were captivating. Building the robotic finger helped students create a "screencastify" video explaining how a real finger bends. They posted their video on Google Classroom and we were able to view presentation skills and evaluate learning. We look forward to the next mystery!”
“Students loved testing out the robot finger to see what it could pick it. Students also engineered some problems: type of string, size of paperclip affects how the robot finger functions. We will wrap this lesson back around and talk about how we can improve our robot finger and what we would need to make it function more effectively.”
“I LOVED that I was able to leave this lesson for a sub! Easy for the sub to follow along, reliable so I knew what the students were doing while I was gone, and engaging, so students were learning and not misbehaving. When I came back, we did the extensions together and they really liked the video. Mixed responses to the dissection :) but it definitely got to the point! ”
“I used card stock paper and it eliminated the step of measuring and cutting the index card. The step by step tutorial was excellent!”
“My students loved making the connections with the dissected chicken foot to their own body and of course the robot finger was a big hit! ”
“For me, the best part was that the students really understood, thanks to the activity, how a muscle works with a tendon to move a bone. Cool!”
“My 2 boys who usually dread science loved it! The activity directions were clear and concise. I am recommending this to everyone! ”
“The students had so much fun playing with their robotic fingers from the activity. I observed some deep exploration happening as they compared the movement of the robotic finger with the movement of their own finger. They also were very interested in the video when it showed how someone could pull the tendons of a chicken's foot to make them move. ”
“Amazing! 20/22 said it was their fave!”
“I liked how it ran smoothly as one big piece. The best part were the video instructions on how to make the fingers. Each step looped until the student was ready for the next step. It made construction easy and freed me up to answer questions based on the content, not on how to make the finger.”
“Loved this lesson. It was so easy to use and to prep and the kids loved making the robot finger. I can't believe how well it worked with just paper and string. It held up really well. The videos were amazing and combined with the activity the children really got the concept being taught. ”
“The students were really engaged and was a great way to teach tendons.”
“My daughters were especially fascinated (and repulsed!) by the chicken foot dissection and loved making a robot finger!”
“The kids were fascinated by the chicken tendons and how they move. They didn't realize they eat muscles when they eat meat. Surprisingly the building of the robot finger went very well and was that challenging for most of the class.”
“WE LOVED THE ACTIVITY! I plan to do this with future classes for sure! ”
“The children were engaged and truly understood how the tendons work with their muscles to move their body.”
“Making the robot fingers and hand was an awesome way to illustrate the concepts of structure & function to the students. ”
“Doing it on Halloween and making the "spooky" skeleton fingers was great- the students couldn't wait to take them home to scare their families!”
“The activity was broken into grade-appropriate steps with just the right amount of challenge in dexterity without frustrating students. Also LOVE LOVE LOVE that the step-by-step instructions loop so students can watch over and over. I did this with a class of 27! WOW! ”
“The best part was making the robot finger. The grossest part was the chicken foot example. YUK! We love you all at Mystery Science.....we stay CURIOUS!”
“My class of 3rd graders loved he mechanical finger AND the chicken foot (we did this in class, too)...what a great way to make a lesson engaging and clear. ”
“The kids were able to connect what they learned about the structure of the chicken leg to a human hand. They then showed in other self guided work that they were able to explain how other animals moved using the information they learned from the lesson.”
“Although my fifth grader already knew some of this, he also learned new things and found the simple breakdown really easy to grasp. My kids LOVED the activity.”
“Loved the robot finger. I decided to do the robot hand with a few of my students but did not realize how attached each of my students would be to their "own" fingers. I never thought I would have to reassure them that "yes indeed you will get your own finger back". ”
“Loved it! Excellent videos with very clear instructions. Students loved making a robotic finger that showed all of the joints. The Robotic Hand video was super cool to watch!”
“The interest level and excitement of the kids was the best part! I loved opening with a question and letting kids generate the vocabulary, make claims and ask even more questions! My kids wanted to know what caused arthritis, what being "double-jointed" meant and if cracking your knuckles was a bad thing. They requested another finger template so they could go home and make another robot finger! Great lesson that was fun to teach!!”
“The exploration was so interesting. We had a great time making the moveable finger. The directions were awesome!”
“My students loved this lesson! I think there favorite part (besides the activity) was the chicken foot. It was a great way to demonstrate how our tendons work. They will remember this lesson, forever! Thanks so much guys! It was a HUGE hit!”
“I love that I can have everything in one place: lesson overview, activities, videos all ready and waiting. The activities' have the replay of each step involved and works great for those who didn't get it the first time. I definitely want more of this!!! ”
“I've tried many hands-on approaches to teaching science over the years, but this is the BEST EVER!!! All materials you need are in one location. Lessons are easy to understand and very detailed. The how-to videos for the activities are the best I've seen. Mystery Science IS my science curriculum for the year!!”
“Great lesson! We really like the guys voice because he has a great way of keeping the kids engaged. The videos of the robots were fantastic!”
“Kids LOVED making the robot fingers. It was a great visual to help them see what goes on to make a finger bend. ”
“The videos as usual are fantastic. Some of my kids were grossed out about the chicken foot (girls mostly) but that's the part that I like. They'll always remember how the tendons made the little toes move!!!”
“This was a great lesson for them. They thought it was so interesting to see the dissected chicken foot with the pulled tendons. They LOVED the activity! They showed their daddy when he got home from work, and then grandparents when they came to visit. This lesson was a huge hit!”
“It was so simple and well explained. ”
“The step by step instruction was so engaging. I don't know who was more entertained, me or my students. Plus, the scientific conversation the students had was incredible. ”
“ It was so easy to follow along and do the activity! Seeing the connection made between what was going on in the video and making the robot finger was amazing.”
“The students listened intently and followed the explicit directions with little help. I appreciate the links to ReadWorks.org.”
“The videos were very informative and easy to understand.”
“The lesson went really well. It was amazing to see my students think deeply and critically over a rather difficult science concept. It supported grade-level expectations and was compatible towards their abilities as 4th graders. Instructions were clear and the lesson was engaging. The lesson also generated several questions beyond the scope of the lesson, which led us to outside research. I believe it is important for students to lead further discovery and this lesson concerning the human body motivated them to do so.”
“The kids loved making the robot fingers and are excited to make a hand. The video with the chicken foot was great, kept their attention and educated them.”
“They LOVED the fingers! It went really well and was super fun!”
“Loved loved loved this lesson. It was very informative and the students loved doing something that seems so futuristic!”
“The chicken model really drove the vocab home.”
“Very well done, informative and kept the students engaged. The robotic finger was so interesting and my class decided to make the full robotic hand. ”
“The chicken leg example was awesome and the kids LOVED the activity”
“The best part was students constructing the robotic finger and hand. Many of their demonstrations were hilarious. Some student's models actually worked. They were able to throw and pick up wads of paper using their model. The activity made the students gain a better understanding of how the hand works.”
“The kids loved the part of the video where they pull the strings on the chicken foot. I liked seeing them move from their predictions that what moves the body is their veins to understanding about bones and muscles.”
“The lesson was interactive and highly interesting from beginning to end. It held my students spellbound every minute!”
“After watching the initial informational video, my kids had ideas of there own on how to build a robotic finger, so they made plans, we gathered materials, and they began working. The next day, we made the finger/hand as you designed it. Many kids revised their own plans. We're going to have a contest tomorrow to see who's hand can pick up the heaviest material. We are also going to disect a chicken leg/thigh in class.”
“Students loved the video showing actual tendons and muscles working (one of my students asked his mom for a chicken foot for his birthday because he wanted to try it!). They also were very excited to try make the robot fingers and hand. They were completely engaged and it sparked many follow up ideas that they are pursuing on their own. ”
“The robot finger activity was supremely engaging and instructive. I modified the robot hand activity to allow all of my students to take a hand home and they loved it. ”
“The students loved the video clip of the chicken dissection. They also loved creating their robot fingers. Their homework was to teach their parents about tendons, bones, and muscles using the finger they created.”
“Truly the best part was watching the students stuyding their own hands for the rest of the day. I could almost see the wheels turning as they thought about their bones, tendons, and muscles. Great lesson!”
“The students loved making a working model of the finger. After every mystery, they want to know what is next, and when we get to do it!! Thank you Mystery Science team!”
“We are now making an entire human skeleton, using the hands and arms from this lesson!”
“Great lesson! My students will definitely remember what tendons, joints, and muscles are and their purpose in our bodies.”
“The students did a great job with lesson and really were able to conceptualize how tendons, muscles and bones are all connected. Also, they LOVED the engineering required for this lesson! ”
“"It was epic." "We won't look at chicken the same way ever again." "Very fascinating!"”
“The kids were so excited about making the finger that some made whole hands at home before we even got done with the one finger at school! They were able to use the terminology to explain what was happening with the model.”
“Needless to say, the kids loved making the robotic finger! The directions were clear and every student was successful. I love the way the video gives a short set of instructions, then loops that the video for that until you choose to forward it. No more "wait...what do I do?" or "I didn't get it!" - the directions are clear, but for those who need to see it again, they can rewatch. I LOVED the "chicken foot" portion of the video - it was (delightfully) gross, but made it very clear how the tendons work, and the students will definitely remember it! Mystery Science lessons are easy to dive into and my students are completely engaged. The videos generate thoughtful discussions and writing, and I like how the students write out assessment responses.”
“The excitement on 5th grader faces. They really thought they knew everything about lesson 1. So many misconceptions cleared up.”
“What an amazing reaction from my students!!”
“The robot finger was a really fun activity, and allowed them to take it home to explain about how fingers move to their parents.”
“The students were ecstatic about their robotic finger. I am planning on the hand next week. They couldn't wait so many of them took home materials to start the hand at home!”
“The kids liked that it could move like a real finger. They loved the chicken toes!!!!”
“My kids loved seeing the dissection and making the robot finger!”
“The students really enjoyed learning about their muscles and "feeling" them as they moved their arms and fingers. ”
“The video showing chicken foot and the tweezer pulling the tendons was diffidently a hit!”
“Since I saw the extra about making the hand, I decided to have that as a finishing activity. I had them crumble up their papers after they cut their fingers out and throw them to the front of the room. Then at the end I had an activity to see who could pick up the paper and put it in the trash the fastest with their robotic hand. It was hard, just like in the video...because there is no thumb. So when I asked how we could make it better next time, several students mentioned making a thumb. ”
“Robot hand was soooo COOL!! ”
“The students really loved and understood how the ligaments, tendons and other parts worked.”
“The kids were SOOO excited, as was their teacher!! It was so easy to understand tendons using the video and then making the robot finger. AWESOME!!”
“Kids loved it. After building hand, now want to build a whole skeleton! I did it with my gifted 2-5 graders.”
“Making the finger was all the rage in my classroom. I let my students do every aspect of the activity and all were successful and proud.”
“We had a blast! The kids were amazed at how their bodies really worked. I loved teaching this unit!! ”
“We enjoyed the video. The kids were able to follow the step by step directions to make the robot finger very easily. Thank you for the great experience!! ”
“Students loved the robotic finger, of course, but also the lesson showing the comparison of chicken parts to human parts! We watched it just before lunch which added to the fun!”
“My students loved this lesson! There was so much discussion! Thank you:)”
“I love how engaging it was with the "robot finger". The kids were so excited to take them home and show their parents.”
“My students LOVED the short videos displayed throughout the lesson...Age-appropriate (on the edge of advanced/edgy) and very engaging. The carefully directed hands-on activity was a new experience for us, and I, personally, am looking forward to the next! This is such an excellent ready-to-go science curriculum...Changing the face of teaching.”
“The robot fingers worked just as they were supposed to and even my students that struggle with hands on projects felt successful.They also really got how the robot finger connected to their own bones, muscles and tendons.”
“The videos were excellent! Not too long, not too short, interesting, yet understandable explanations. I really loved the faithfulness to science, no cartoons or gimmicks, but a real dissection! The kids loved to hate the chicken foot demonstration. The hands-on activity was incredible. Finally, there was practically no prep on my part. That hardly ever happens, usually I have to doctor lessons up to make them more interesting or accessible to my students. Thank you!”
“The students were better able to explain how muscles, bones, tendons, and joints all work together, after making the robotic finger and hand.”
“I loved the step by step directions as it made classroom management so much easier.”
“The kids loved making the robot fingers and hand; again a hands on activity that brought their learning to life. ”
“The videos kept my students' attention the entire time and they loved discussing the questions at the end of each segment. ”
“My kids absolutely loved the chicken hand video and making the finger!”
“The students loved making the finger, next time we will make the hand. Very helpful on understanding how the hand works.”
“I did it with second graders and the activity was difficult for them to do. They got a lot out of it though. They could use the finger to explain how a real finger actually works. They all wanted to build the hand!”
“The students loved making a model of the finger. As homework, they had to go home and teach it to a family member. The parents are loving how much their child is learning through the Mystery Science lessons. Thanks!”
“Making the robot finger. Also,,,the chicken foot! The kids were amazed by that!”
“Wow! We had so much fun learning about the human body, and the chicken foot...Holy Moly!! This has been the best mystery yet!”
“This was easily one of our favorite activities! My daughter loved the robot finger so much that we had to make the hand. The dissection was a wonderful visualization, as well, and one we don't tend to get the opportunity to see at this age. I doubt my daughter will ever be able to watch me cut up chicken again without reminding herself about tendons and muscles. Fantastic work!”
“My kids couldn't wait to get home to show their parents their robotic fingers!”
“The kids loved making the robotic finger! We are planning to tackle the hand tomorrow. The discussion was very helpful in keeping the kids engaged. I was worried about the chicken leg, but they loved it!”
“The kids loved the demonstration and being able to understand that muscles are what helps us move and building the movable finger. We love Mystery Science, the kids are engaged the entire time. We have to look up so much more because it creates so many questions!! Love, love, love this program!”
“Oh my they love the fingers! They are now on a mission to collect enough cereal boxes to make hands on Friday! We have talked our principal and leadership team into purchasing your program! Keep the awesome lessons coming!”
“Watching the class try to work out what made their fingers move! They also loved the Robot Finger activity and it worked really well. I had all of the resources I needed in the classroom.”
Lesson narration:

Grade 4

Human Body, Vision, & The Brain

Muscles & Skeleton

4-LS1-1

Activity Prep

Print Prep
In this lesson, students discover the mechanism by which their muscles control their bones to move their bodies. In the activity, Robot Finger, students construct a model of a human finger and observe how pulling on a string (a model for tendons) causes it to bend at the joints.
Preview activity

Exploration

25 mins

Grade 4

Human Body, Vision, & The Brain

Muscles & Skeleton

4-LS1-1

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Body Lesson 1: Why do your biceps bulge?

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