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Meet the Micro:bits
Coding is easy and fun when students meet the micro:bits. Learn to write and download code, so you are ready to create your own scientific tools!
Meet the Micro:bits
Coding is easy and fun when students meet the micro:bits. Learn to write and download code, so you are ready to create your own scientific tools!
Student Edition
(English/Spanish)
Student Edition
(English/Spanish)
Student Edition
(English/Spanish)
California Wildfires
Watch Class Movie
teacher Prep
Lab sheet & activites
Class Movie
Watch Class Movie
Class Movie
Teacher Prep Movie
Lab Materials Needed
Blockey Koa Crate
from Kea STEMCrate
- 1 Springy Spring Scale per student
Student Lab Sheet
Using a Punnett Square: Predicting Variation in Genetic Traits
Student Edition
(English/Spanish)
Teacher Edition
(English/Spanish)
From Molecules to Organisms: Structures and Processes MS-LS3-2:
Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation. [Clarification Statement: Emphasis is on using models such as Punnett squares, diagrams, and simulations to describe the cause and effect relationship of gene transmission from parent(s) to offspring and resulting genetic variation.]
From Molecules to Organisms: Structures and Processes MS-LS3-1:
Develop and use a model to describe why structural changes to genes (mutations) located on chromosomes may affect proteins and may result in harmful, beneficial, or neutral effects to the structure and function of the organism. [Clarification Statement: Emphasis is on conceptual understanding that changes in genetic material may result in making different proteins.] [Assessment Boundary: Assessment does not include specific changes at the molecular level, mechanisms for protein synthesis, or specific types of mutations.]
Pacing Guide:
Color Key: Green words- Hands-on Activity Black words- Book reading Blue words: Revisit the Phenomenon
Instruction day 1: Explain the Phenomenon
Summary: Introduce Punnett squares by creating a creature with a mix of genes!
Lesson Objective: Students use a model to represent the inheritance of dominant and recessive genes.
Distance Learning adaptation: Print the PDF of character cards for your students to pick up from school or have them cut out squares of blank paper on their own and write out the traits in ALL CAPS or all lowercase using the cards as a model. Students can put each Body Shape card in it’s own bag to be pulled from, use another bag for Body Size and another for Color. Students pull one from each bag for the mother and write it down, then one from each bag for the father and write it down. Use the rest of the directions below to determine how a student’s Monster Baby will express its genes and what characteristics are found for the class as a whole.
Materials Needed: scissors, two paper bags or bowls
Introduction: Do you know what the word “dominant” means? (To be stronger than something else.) Dominant is a word we’re going to use a lot in our new chapter, as well as “recessive”; when we talk about genes “recessive” means less strong. Today we’re going to make a creature using different genes; some are dominant and some are recessive. Let’s make a monster!
Instructions:
-Students cut out the twelve cards that say SQUARE, circle, LARGE, small, ORANGE, green. (Two of each type.)
(with cute character drawing backgrounds)
Punnet Squares
introduction activity
-SQUARE and circle cards will go into a container labeled “Body Shape”, LARGE/small cards go into a container labeled “Body Size” and ORANGE/blue cards go into a container labeled “Body Color”.
-Once every student’s squares are in the containers then they get shaken up and each student picks out one card from each container without looking.
-Students head back to their desks and write down all three of the traits they picked in the boxes labeled “Mother Gives” in their journal.
-Those cards remain at their desk while they come back up to pick another three cards, one from each container, this time to be written under “Father Gives”.
-Students look at the third row “Gene Expressed” and write down the dominant gene for each column. If either the mother or the father gave a DOMINANT gene then that gene is written down for Gene Expressed. If both the mother and father had a recessive gene then it is written down.
-Take a class poll: How many had SQUARE baby monsters? How many had circles? How many had LARGE? Etc. Students write down the total number of each for each category.
-Students answer the last question to the best of their ability.
(Rough version of what will be in text)
Class totals for genes expressed by Baby Monster:
SQUARE: ____ circle: ____ LARGE: ____ small: ____ ORANGE: ___ blue ___
Explore the Phenomenon question: Can you explain it? What do you notice about dominant and recessive genes?
Guiding Questions:
Ask: What do you think is meant by “Gene expressed by Baby Monster”?
Example: I think it means that the Baby Monster’s body picks that trait to make instead of the other trait. My Baby Monster got one SQUARE gene and one circle gene so as it grows it will have a square-shaped body instead of a circle-shaped body.
Ask: What happens if both parents pass on the same gene? What happens if they pass on different genes?
Example: If they pass on the same gene then the baby has that gene. If they pass on different genes then the baby expresses the dominant gene of the two.
Ask: Compare your monster to your neighbors’. How are they the same? How are they different?
Example: Most of my friends' monsters have the dominant genes expressed, but a few of them have some recessive genes.
Wrap-up: Draw your Baby Monster! If you have space, add your neighbors’ monsters too. What would baby monsters be doing?
Instruction day 2 (pages 161 - 162): Read and discuss
Summary: Discuss gene expression and dominant versus recessive genes.
Lesson Objective: Students understand that babies get their genes from their parents and one of those genes is expressed. Students discuss the difference between dominant and recessive genes.
Introduction: Look at the cover of the article, what do you notice about the picture? (There is an adult and a young horse, probably mom and baby.) What do you notice about the color of the horses? (The foal looks more lightly colored than its mom. Maybe its dad had lighter colored hair.) Let’s see how genes can affect what color a horse can be.
Instructions: Read pgs 161 and 162. Observe the picture and diagram, ask students what they notice. Have students talk to each other about how to define each of the blue vocabulary words and write those definitions in the margins.
Guiding Questions:
Ask: When we look at the picture we notice three dark cats and one white cat. Which color do you think is dominant? Why?
Example: I think that the darker color is dominant because there are more dark cats than white cats.
Ask: When two parents have a baby, they each give that baby half of their genes. The two halves come together to make a whole new baby with a different mix of genes. Where did the parents get their genes from?
Example: The parents got their genes from their parents, who got theirs from their parents too, going back generations and generations.
Ask: Have you ever had something in common with a grandparent?
Example: My grandpa and I both have big ears!
Wrap-up: Pair/share prompt: What are some physical traits that are common in your family?
Instruction day 3 (pages 163 - 164): Read and discuss
Summary: Either of your two genes can be dominant or recessive. We use letters to represent both possibilities.
Lesson Objective: Students understand that all genes can be characterized as either dominant or recessive. Students discuss that though an organism may be expressing a dominant gene, it is possible they also have a recessive gene. Students understand this recessive gene can still be passed down to offspring.
Introduction: We’re talking about tail genes being passed down from parents to offspring. A lot of times offspring will look like their parents, but sometimes they can express different genes than their parents do depending on which genes the parents passed on to that particular offspring.
Instructions: Read page 163 and discuss the drawings at the bottom of the page. Read page 164 and discuss how capital letters are used to represent dominant traits and lowercase letters are used for recessive traits. Have students use the margins to write down any notes that will help them in the future.
(Teacher note: some of the older texts use the word “dominate” instead of “dominant” several times; this is corrected in a future edition.)
Guiding Questions:
Ask: The mom animal has two tail-type genes, one gene is for a poofy tail and one gene is for a long tail. Why is it that we only see her with a poofy tail and not a long tail?
Example: Her tail is only poofy, not long, because poofy is the dominant gene.
Ask: Why do you think scientists use capital letters and lowercase letters?
Example: It is easy to see which one is dominant and which is recessive.
Remember, the actual letter is not important, it is just representing a gene. Writing “Hh” is shorter than writing out “Dark hair gene” and “Light hair gene”.
Wrap-up: Watch YouTube video about dominant vs. recessive genes (2 minutes). Warn students beforehand that the video uses the term “alleles”, this is a word they don’t need to know for this chapter, they can think of the word as meaning “genes”.
Instruction day 4 (pages 165 - 166): Read, write, and discuss
Summary: How do our bodies decide which genes to express?
Lesson Objective: Students discuss the circumstances in which dominant and recessive genes are expressed. Students are introduced to the idea of a Punnett Square to be used for prediction.
Introduction: Imagine you have two bowls of ice cream in front of you. Which do you like better, chocolate or vanilla? If you chose chocolate then every time you have a choice between those two different bowls of ice cream, you would pick chocolate, it would be the “dominant” choice. If you had two bowls of chocolate ice cream to choose from, that would be easy, either one! If you had two bowls of vanilla ice cream and no chocolate, you would probably still take the vanilla because hey, ice cream is ice cream! Your gene expression acts the same way. Of the two genes you have for eye color there is a preference for one gene over the other, unless they are the same. The preference is the gene that is expressed.
Instructions: Read the top of page 165. Use the two rules to determine how to draw the tails for each critter. Use the letters on their bodies to help answer the questions in the blue circles.
Guiding Questions:
Ask: There are four possible combinations of the two tail genes. The gene from the mom could be recessive or dominant and the gene from the dad could be recessive or dominant. Even with all those possible combinations, how come only one of the critters has a long tail?
Example: All the other critters have at least one dominant gene for a poofy tail, the long tail is only made if both of the critter’s genes are the recessive long tail gene.
Ask: What is the difference between possessing a recessive gene and expressing a recessive gene?
Example: A critter may have a recessive gene, but we don’t see it expressed unless there are no dominant genes to overpower it.
Ask: Do you think that one of the three critters with a poofy tail could ever have a baby that has a long tail?
Example: Either of the critters with one dominant and one recessive gene could possibly pass on their recessive gene for a long tail. They still have it, even if it is not being expressed by their body.
Take-away: Written in your DNA you have two genes for every trait. One you got from your mom and one you got from your dad. Whether those genes are the same or different, only one of them is expressed by your body.
Introduction for Second Page: When it comes time to pass on your genes to your children you are just as likely to pass on either of your genes! Even if you have one dominant and one recessive gene and your body only expresses the dominant trait, you are still 50% likely to pass on your recessive gene to your children. There is a cool way that scientists can show how likely it is that offspring will have or express that trait. Let’s learn how to make a Punnett Square! You’ll be making your own later so let’s see what the steps are. (Read the page together and move on to the next pages when ready.)
Ask: We’re going to use this special square to show you all the possible outcomes of the offspring. Why can’t we predict exactly?
Example: We can’t predict exactly because it is just a chance of which gene could be passed down. Just like flipping a coin, it is possible that the same gene gets passed down to all offspring.
Wrap-up: Pair/share prompt: Do you know any groups of siblings that are half boy and half girl? What about all boys or all girls? We know there is a 50% chance a baby will be born as a boy or as a girl, but that doesn’t mean that one family will always have half and half.
Instruction day 5 (pages 167 - 168): Read, write, and discuss
Summary: How to label a Punnett Square.
Lesson Objective: Students follow the steps for creating a Punnett Square.
Introduction: In the previous pages we introduced the shape of our special square that will help to show us the possibilities of how a mom and dad’s genes could mix in their offspring. Let’s see what our next steps are.
Instructions: Read on page 167 how scientists label the outside edges of a Punnett Square. Read on page 168 how the inside of each square should be labeled with both the gene from the mom above it and the gene from the dad to the left of it. These four squares represent every possible tail gene combination a baby from this mom and dad could have.
Guiding Questions:
Ask: Why don’t any of the squares have two big “T”s together or two little “t”s together?
Example: Each square needs to have one gene from the mom and one gene from the dad. The mom only has big “T”s to give, the dad only has little “t”s to give.
Wrap-up: Pair/share prompt: Do you have any predictions about the tails the babies will have that come from this mom and dad? Write your prediction in the blue margin.
Instruction day 6 (pages 169 - 170): Read, write, and discuss
Summary: Punnett Squares are used to predict the likelihood that offspring will express certain traits.
Lesson Objective: Students understand how each square represents a 25% likelihood of offspring having that genetic combination and helps us predict the probability of a trait being expressed in offspring. Students apply their knowledge to a new Punnett Square. Students use the model to predict the genetic variation of the critter.
Introduction: We’ve learned how to fill out a Punnett Square, now let’s see how to use it to make predictions!
Instructions:
-Read page 169 to understand why every possible genetic combination results in all the offspring having the same tT genes. Use the Guiding Questions below before moving on to the next page.
-Read the directions on page 170 for students to fill out a new Punnett Square.
-They put one letter into each blue circle, making one pair of circles the mom and the other pair of circles the dad.
-Put the correct two-letter combinations into each of the four squares, using the letters they put in the circles as a reference.
-Use the margins to write out which squares have a dominant T gene and which only have a recessive t gene.
-Each square is still worth 25%, but have students add up the total percentage of dominant and recessive tails.
Guiding Questions:
Ask: Why is each square given a value of 25%?
Example: Each square is 25% because each square has a one in four chance of happening. 25% is the same as ¼th.
Ask: Why does it say that 100% of the critters have the tT for their tail?
Example: In this case, each square is the same so all those 25%s are the same. If all of them are the same then each baby has a 100% chance of a tT tail gene overall.
Ask: What if we were doing this example with different genes from the mom and dad? Would each square still be worth 25%?
Example: Yes, 25% is ¼ and each square is just as likely to be passed on to the baby as any other square.
Wrap-up: Watch a TedEd video about Punnett Squares (3 minutes). (Warn students they don’t need to worry about words like “phenotype” or “heterozygous”, just watch the animations and use them to help understand the previous pages.)
Instruction day 7 (pages 171 - 172): Read and discuss
Summary: What causes mutations? Are they good or bad?
Lesson Objective: Students discuss the cause of mutations. Students discuss the possibility that a mutation could lead to a negative, positive or neutral outcome for the individual.
Introduction: Have you ever heard of Teenage Mutant Ninja Turtles? What is different about them from turtles you’d find in nature? (They have big muscles and can walk around on two legs. They wear bandanas, know ninja moves and fight bad guys!) Does anyone know how they became mutants? (They were pet turtles from a pet store and got covered in chemical goo that transformed them.) While that isn’t something that could happen in real life, the true thing is that an event can cause a change in DNA. That event is just a lot smaller than a big messy chemical spill!
Instructions: Read both pages, check out the picture of a Manx cat and read the poem in limerick rhythm.
Guiding Questions:
Ask: What do you think it means by a gene not being perfectly copied during cell division?
Example: I think it means that when a mom passes her genes to her babies she starts by dividing her cells. We learned in the previous chapter there are lots and lots and lots of genes for every organism, so maybe there are some mistakes when all those genes get copied by the cell.
Ask: When a gene is copied incorrectly, but that gene is then passed on to the baby, there are a few possibilities of what could happen to that baby. Maybe its new genes will help it be better camouflaged so it can survive better. What other possibilities can you think of?
Example: (Steer students towards acknowledging that some mutations are bad enough that the baby won’t survive well in its environment, or the mutation could help them survive better than their parents, or that the mutation won’t affect its ability to survive at all.)
Ask: Mutations that are bad for animals (like being an albino instead of having camouflage) are pretty rare to see, can you think of why?
Example: If a mutation is bad then that animal probably won’t live long enough to reproduce and pass on its bad mutation to future animals. An albino animal is more likely to get eaten by a predator early in its life. But it's possible for some to survive despite the odds!
Wrap-up: Pair/share prompt or class discussion: They say that the stubby Manx tail is dominant so if a Manx were to have kittens with a long-tailed cat, would more of the kittens have stubby tails or long tails? (More would have stubby tails than long tails.) Why do you think we don’t see more stubby-tailed cats then? (We have way more long-tailed cats than stubby tailed cats because the Manx cats all live on an island.) What do you think would happen if someone let loose a lot of Manx cats in an area with other pet cats that could have kittens? (It is possible that they could reproduce and pass on their stubby-tail dominant genes in that new area.)
Instruction day 8 (pages 173 - 174): Hands on activity: Make you own Critter
Summary: Show what you know! Give a critter characteristics and determine its Punnett Square.
Lesson Objective: Students demonstrate understanding by creating their own creature and picking a trait to have both a dominant and recessive gene. Students work to label and complete a Punnett Square based on their creature.
Introduction: Now you get to make your own crazy creature! You can give it as many characteristics as you want, but you will pick one of those characteristics to make a Punnett Square about. Then you can use the Punnett Square to show how it passes its traits onto its babies.
Instructions: Have students either draw their critter first or write about it first as they are comfortable. Read the directions and fill out the top of the second page. (Use Guiding Questions if needed.) Have students decide which 2 genes are coming from the mom and which 2 genes are coming from the dad to label the sides of their Square. (At least one of the four total genes from the parents should be different; all 4 recessive or all 4 dominant won’t demonstrate learning.) After students fill in the squares with the passed on genes, they should evaluate their findings based upon each square having a value of 25% and write about what they notice being passed on to future offspring in the blue square provided.
Guiding Questions:
Ask: Will someone give me an example of a characteristic of your critter that you are having a dominant and recessive gene for?
Example: My unicorn can have a short horn or a long horn. My pegasus can have sparkly wings or fluffy wings. My Godzilla can breathe fire or breathe ice.
Ask: How would you fill out the line labeled “Trait Name”?
Example: Unicorn: horn length. Pegasus: wing type. Godzilla: breath type.
Ask: Which trait do you want to be dominant? How are you going to indicate that? How will you indicate the recessive trait?
Example: Unicorn: long horn = H, short horn = h. Pegasus: sparkly wings = W, fluffy wings = w. Godzilla: fire breath = B, ice breath = b.
Wrap-up: Pair/share prompt: What if your critter had babies that had a mutation? How could it be different from its parents? (My Godzilla’s babies mutated so that now they can blow tornadoes!)
Instruction day 9 (page 175): STEM Vocabulary
Summary: Discuss terms learned in the chapter.
Lesson Objective: Students review vocabulary words learned in the chapter.
Introduction: We learned a lot about genes in this chapter, let’s make sure we don’t get it all confused.
Instructions: Note each of the blue words and have students go back to look at their notes about them in the chapter. Students can give an example of the word, write something interesting about it or define it in their own words.
Guiding Questions:
Ask: If I were a critter with one dominant gene for a poof tail and one recessive gene for a long tail, which gene would be expressed? What does that tell us about gene expression?
Example: The dominant poof tail would be expressed, even though you also have a long tail gene. Gene expression is which gene your body expresses of the two possibilities.
Ask: How can a recessive gene hide through generations, not being expressed then suddenly appear in future offspring?
Example: If the recessive gene is paired with a dominant gene then you won’t see it expressed, but it can still be passed onto future generations. If they have babies with another organism that passes on the same recessive gene then it can show up in grandkids or great grandkids!
Ask: Are gene mutations always bad?
Example: No, sometimes they can be helpful and the organism can better survive, or they can be neutral and not have an effect on the survival of an organism. An example of a mutation could be how many domestic animals (cats, cows, dogs, chickens) can have a wide variety of colors, but because humans keep them protected from predators the colors don't strongly impact the ability of the animal to survive.
Wrap-up: Do you still have any questions about the ideas we’ve learned?
Instruction day 10 (page 176): Hands on activity: Program a Punnett Square
(Editor Note): This activity is labeled Intermediate difficulty. Give your class the appropriate amount of time to complete this activity based upon their previous experience using Scratch.
Summary: Use a computer to model a Punnett Square.
Lesson Objective: Students use programming skills to create a computer model for Punnett Squares.
Introduction: You get to be a programmer! We’ll learn how to move our critter around and build a Punnett Square using code.
Instructions: You can follow the directions in the text for students to navigate to the website or use this link here: https://www.stemtaught.com/g6punnettsquareanime, password = yay (all lowercase). There you will find this video tutorial on how to complete the coding activity (10 minutes). We recommend you project the video for the class to see while programming; pause the video often to make sure students are following along with the steps. Students may help each other to make sure they are on the same page. (The layout has changed on Scratch since the making of this video, but the options are still the same.) Once programmed, students can use it to experiment with several different Punnett Square options.
Guiding Questions:
Ask: Where are you having your critter place its eggs?
Example: There needs to be one egg above each column (representing the genes mom can pass down) and one egg to the left of each row (representing the genes dad could pass down). Inside each box I’m putting two eggs to represent the two genes the offspring will get.
Wrap-up: Pair/share prompt: Would you want to try programming this activity any differently?
Instruction day 11 (page 177): Writing Workshop
Editor’s Note: Older textbook versions do not have this writing workshop printed on page 177, please provide your students with the following scenario:
Summary: Use a pet as an example for writing about how Punnett Squares are used.
Lesson Objective: Students use writing to demonstrate understanding of the chapter.
Introduction: What if your pet had babies? Let’s write about how a Punnett Square could work for a pet. You could even use an imaginary pet if you like!
Instructions: Students write about the dominant and recessive traits of an organism to demonstrate knowledge of how to use a Punnett Square to predict variation. Students describe how Punnett Squares are used and how they help explain the passing down of dominant and recessive traits. Students are encouraged to create a Punnett Square example to refer to in their writing.
Guiding Questions:
Ask: How do Punnett Squares help us understand how recessive traits can get passed down to future generations, even if they are not expressed in the parents?
Example: Punnett Squares show us that a parent can have a recessive trait, even if their body only expresses a dominant trait. They can pass that recessive trait onto their children and it could be expressed if the child’s other parent also has a recessive gene that is passed onto them. Or it could stay hidden by a dominant gene and then get passed down to the grandkids of those first parents.
Ask: If a parent has two genes, one dominant and one recessive, what is the chance that they will pass on their dominant gene to their offspring? What are the chances that they will pass on their recessive gene?
Example: The chances are 50% for both. Either gene could be passed on, but in general dominant genes are more likely to be expressed in a population because they are favored.
Wrap-up: Pair/share prompt: What was the most surprising thing you learned in this chapter?
Instruction day 12: Evaluate
Google Forms Quiz: Teachers can access what students understand through this google forms quiz.
Click the link to copy this google form into your personal Google classroom.
Click the link to copy this form into your Google classroom.
*No password is required for the quiz*
Coding Activity: Programming Tutorial
Programming Tutorial:
Interactive Punnet Square
Students create an interactive Punnet Square.
Click on the picture to access the coding activity.