If you asked biology students about their favorite unit, many would enthusiastically choose heredity. For some, it’s a topic they fondly remember tackling in middle school, and even those new to it often grasp the basics quickly. With a strong foundation, students typically feel confident and eager to take charge of their learning as they dive into practice problems. That confidence, however, can sometimes be misplaced. If we focus solely on straightforward question setups and repetitive Punnett square drills, students may miss the deeper, analytical aspects of the unit—or struggle with the complex, wordy scenarios they’re likely to encounter on assessments. In this blog, I’ll share my approach to teaching heredity, blending engagement with inquiry-based strategies to ensure students not only enjoy the unit but also master its challenges. The Order I Follow In high school, students must master both Mendelian and non-Mendelian genetics. To wrap up the unit and bring everything together, they tackle the most mind-bending (but incredibly rewarding!) concept: pedigrees. Here’s the progression I use to structure my heredity unit:
In this blog, I’ll break down each lesson, share how I approach it, and explain why I teach it the way I do. Lesson 1: Start "Slow"
Lesson 2: Time for Punnett Squares Sticking with the philosophy of "slow and steady wins the race," it’s finally time to dive into Punnett squares. Of course, we start with the "standard" dominant/recessive inheritance—no teacher would begin with anything else! Mastering these foundational crosses is crucial, as they form the basis for understanding more complex inheritance patterns. I emphasize to students that while the terms "autosomal" and "monohybrid" might sound intimidating, breaking it down helps them feel more confident. After all, most Punnett square problems are presented in sentences, so students need to become comfortable with the vocabulary to avoid being thrown off. To solidify their understanding, I deliver a concise 20-minute lecture followed by multiple-choice practice questions. At my school, our grading platform lets me create automatically graded bubble sheets that upload scores directly into the gradebook. This real-time feedback allows me to quickly identify students who need intervention and those ready to move on to the inquiry-based activity. For differentiation, you may want to give struggling students a non-inquiry (practice-based) worksheet. Once students grasp these foundational crosses, they’re ready to tackle something more engaging. Too often, the mathematical nature of Punnett squares causes teachers to shy away from inquiry-based learning in this unit. However, it’s crucial to show students that heredity, like all scientific principles, can be applied to real-world scenarios—even magical ones!
Lesson 3: Not my favorite either... Dihybrid crosses—the part of genetics that makes students' eyes widen with dread. Since these aren't typically covered in middle school, they can initially feel overwhelming. Students need to learn how to determine parental gametes for two traits (using the FOIL method) and interpret a 16-square Punnett square. However, it's important to know they aren’t required to perform these crosses from beginning to end on state tests. While it’s beneficial for students to complete a couple of dihybrid crosses from start to finish, the real focus should be on two key skills that are tested: mastering FOILing to determine gametes and identifying phenotypes from genotypes when working with four-letter combinations instead of two. This ensures they grasp the essential concepts without unnecessary overwhelm.
Lesson 4 and 5: Sex-Linked Traits & Non-Mendelian Genetics In an ideal world (which I don’t live in), I’d have 45-minute classes for this unit. I’d dedicate one class to non-Mendelian genetics (with practice questions), another to sex-linked traits (also with practice questions), and then two additional 45-minute classes for my aligned activities (details below). This setup works beautifully because both activities incorporate sex-linked and non-Mendelian principles. In reality, I teach block classes, which means 90-minute sessions. If you’re in the same situation, I recommend starting with non-Mendelian genetics first. Why? The aligned activity only includes one sex-linked trait at the beginning, so you can guide students through it together before they dive in.
For sex-linked traits, I keep it simple and focus only on X-linked inheritance (since I’ve never seen a Y-linked question on state tests). The biggest challenge for students? Remembering to include X and Y chromosomes in their Punnett squares. After finally mastering it, many struggle to switch back to regular annotation for autosomal traits in the next class. That’s why one of the key takeaways from this lesson is learning to carefully read questions and identify phrases like “autosomal,” “sex-linked,” or “carried on the X chromosome.” A well-written question will always provide these clues, signaling whether X and Y annotations are necessary. To reinforce this, I designed my sex-linked practice questions to include both autosomal and sex-linked examples—be sure to explain this distinction to students if you assign my questions.
Lesson 6: Finish Strong Pedigrees can be particularly challenging for students because they require a deeper level of thinking—backcrossing, test crossing, and analyzing multi-generational data to solve problems. A common misconception is that pedigrees are exclusively for X-linked traits. This likely stems from the frequent use of examples like the Victorian hemophilia family in teaching. It’s crucial to emphasize that pedigrees can track any trait—dominant or recessive, autosomal or sex-linked. The shaded symbols simply indicate the phenotype being tracked (so it could be dominant or recessive), and the inheritance pattern depends entirely on the question at hand. Overall, the complexity and integrative nature of pedigrees make them an excellent capstone lesson for the heredity unit, tying together all the key concepts students have learned. Try switching things up by saving the multiple-choice questions for last, after the aligned activity. Letting students dive into a fun, creative challenge first can build their confidence with this tricky concept before tackling the more straightforward, disconnected questions.
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Last year, I created the Insane in the Membrane Game, and after using it with my students, I took their feedback to heart—just like most teachers do—and made a few key improvements! I'm excited to share the updated version of the game with you, along with tips on how to set it up and play it with your own students. It’s been a huge success, and while I don't have a lot of action shots (thanks to a dead phone!), trust me—it was a hit! When and how does it fit into a Biology curriculum?I teach from micro to macro, so Cell Structure & Function is the second unit of the year. My lessons follow this sequence:
That's why I created the Insane in the Membrane game. In this activity, students physically move molecules across their cell membrane game board, practicing these concepts repeatedly. This hands-on experience helps solidify their understanding and transfer the material into long-term memory. The follow-up questions reinforce key standards while reviewing the structures and functions of the cell membrane from the previous lesson. Materials and PreparationThis lab does require a little bit more prep the first year because the playing cards for each group need to be printed, laminated (optional), and cut. Once that is done, each group of four students will have the following materials:
I do think it's important for you to read through the Insane in the Membrane Directions below prior to the day of the game. It's definitely not hard or complicated! The student who reaches equilibrium in all four molecules first wins. The Day Of...This lab activity will take students roughly 40-60 minutes to complete. Each group should have the materials already set out and ready to go (this will help cut down on time!). Here is the breakdown:
Pre-Activity and Board Set-up
Here are the Directions...Playing the GameI personally go over the gist of the game with them. It only takes a minute to explain. They always get a hang of it within the first 5 minutes of playing. Last year I played this game "Candy Crush style." Students would pull one card out of the bag at a time and follow the directions. For the most part - it was just the luck of the draw. Student feedback was that they wished there was some sort of strategy. This year I made the game more "Uno-style." This means students always have 5 cards in their hand and they can choose which of the 5 cards to play and when. This went WAAAAAAAY better. Sometimes I have students And that's basically it! Students answer the post-lab questions (which you can modify). Let me know how your students liked the game and don't hesitate to contact me with any feedback or questions at [email protected]. Have fun! Links to this product and related products...
Background Last summer, I invested in several courses to improve my skills as a TPT seller, focusing on how to create high-quality products that teachers genuinely need. Throughout the courses, one platform kept coming up that I hadn't heard of before—BOOM Learning. Initially, I assumed it was more suited for elementary education and might not be relevant to my high school teaching. I’m so glad I was wrong! After exploring BOOM Learning, I was thrilled to incorporate new resources into my high school curriculum. From engaging reviews to interactive escape rooms, BOOM Learning offers a refreshing alternative to the usual, uninspired worksheets often given to older students. About the BOOM Learning Platform
Using BOOM to Review for AP Environmental Science Reviewing for the APES exam is essential. The vast amount of material covered ensures that even the strongest students will inevitably forget some of it. So, how can we effectively review? Practice questions, flashcards, worksheets, YouTube videos, and games are all useful methods, but each fall short in some way. I made a short video to explain how I use the platform to create self-paced, interactive resources... By using the Flow Magic feature in the studio, I created review materials that:
How do I implement these in the classroom? My students can work independently or in pairs to complete the reviews. I find that when students collaborate, they tend to need less assistance from me, as two minds are often better than one. I have my students complete the BOOM reviews before every test, and then we revisit them just before the big exam in May. Additionally, we focus on FRQ training throughout the year. Altogether, I now do three things for my own "ultimate review" - the BOOM reviews, FRQ practice (which includes grading), and 3-5 full-length practice tests. The results are significantly boosted my test scores! While test scores aren’t the real measure of success, in my opinion, we all want our students to get those college credits. ![]() Here is my all-in-one-money-saving bundle. It includes units 1-8. All I have to do is add unit 9, which I will do sometime in January or February. If you bought the curriculum or activities bundle, it's already in the drive. I have gotten a few emails from people who aren't using them because it "costs money" to use the platform. I assure you it doesn't! I will end by saying that BOOM Learning is trying to cut down on unauthorized sharing by essentially punishing the seller. Each time a teacher activates my resource on BOOM (i.e. puts it into their library) without purchasing it themselves, I am charged 10% of the original price. PLEASE do not share my BOOM reviews with your colleagues. If I keep getting charged, I will have to discontinue everything I have built, which would be devastating. I truly appreciate your professionalism and respect for copyright.
Definitely let me know in the comment section or by email ([email protected]) if you have any questions, suggestions, or feedback! I do have an email list if you would like to get notifications of new products, blog posts, or TPT sales. This lab is not only a staple in Biology, but it is a student favorite. In my very first blog (YAY!), I would like to share with you my version of the last meal macromolecule lab, which is set-up as a forensics who-dun-it murder mystery. Although the concept of the lab isn't new, I wrote this entire activity from scratch years ago. As teachers, we continually tweak things to make them better, and I've finally reached a point where I'm 100% happy with this lab. By blogging, I hope to expound on my labs and activities to help you gain some confidence and insight before bringing it into your own classroom. You can follow the link to the lab and download the preview, which includes the backstory (Eugene's murder), the directions, and the student hand out.
I would be lying though if I said online labs and activities were a lesser version of actual hands-on labs. I think in a lot of ways they are better. As you can see from the YouTube trailer, students are able to self-pace their way through the lab, which is split up into 5 parts that mimic a 5-E lesson. This, combined with the fact that it is self-grading and interactive, means students really do learn effectively. Plus, there's no prep, clean-up, or grading, which is amazing! Onto my hands-on version of the lab! There are other murder mystery macromolecule labs online, and they have you buying potatoes and eggs and all sorts of groceries and then blending them up to create your solutions. I HIGHLY suggest simply ordering dried versions of the macromolecules that you can just add water to - plus, because they are dried, you can keep them year after year in your storage cabinets. I have a picture of the ones that I ordered from Amazon. At this point, the fructose and gelatin are three years old! Below I have pictures of the positive controls (left) and the stomach contents (right), which is a combination of fructose, gelatin, and red dye. I know this is going to seem like a waste to some people, but for messy labs like this, I opt to use small plastic cups instead of beakers. My classroom is oooooold and I do not have large lab desks that I can set-up as stations. Plus, I teach very squirrely freshman. For safety purposes, I have my students work in pairs with their butts in their chairs for almost the entire lab. The only time they will need to get up is to put their tests tubes in the hot water bath for the simple carbs test and to rinse their test tubes out between macromolecule tests (I do have 5 sinks around the room). Having my lab set-up this way requires a little bit more prep, but remember, you could have one station set up for each test and have students rotate around the room. I have pictures below of how I do it. Each pair of students will have 6 small cups containing water, fructose solution, starch solution, oil, gelatin solution, and stomach contents. I line the cups up like the picture below, fill up a large pitcher of one of the solutions and just pour all the cups in that row. It goes pretty fast. As you can see, I put a little green string and a pom pom ball in the stomach contents and call it seaweed and fish eggs for fun ;) You can see each partner set-up below. Each of the 6 cups gets its own plastic pipette. Each pair will also get three glass test tubes labeled "+" for the positive test, "-" for the negative test (always water), and "S" for the stomach contents in a test tube rack. Each desk gets the four indicators (Benedicts, Biuret, Lugol/Iodine, Sudan III) in dropper bottles and some Lysol wipes. I also took a picture of what I write on the board when I go over the lab with students. The tests are pretty straight forward. I took these pictures last year and have switched up the storyline slightly. This year, the stomach only has simple carbs and protein in it but the picture below shows a positive result for complex carbs (which it won't if you use my new updated version). I would say the only tips and tricks I have is:
What about the flow of the entire lesson? I teach 90-minute classes, so for me it is easy to do a PowerPoint and this lab all in one class period. If you teach 45-minute classes, you could teach the PowerPoint and do the front page of the student lab handout one class period, and then have students do the Last Meal Macromolecule Lab the following class period.
I teach my students an introductory lesson on macromolecules while they take guided notes. My personal preference is to go over the pre-lab questions as a class (hand-raising). Then I call on students to each read a paragraph of the backstory. I find that student engagement is enhanced if we all read it together. From there we actually go over the Backstory part of the worksheet. I want to make sure students know what macromolecules were in each of Eugene's meal before they start. I am big into gradual release. Finally, I go over the gist of the lab with them and let them perform the tests on their own. Remind them not to shout of who the murderer is since they will all be finishing at different times. I hope you found some of my tips helpful! Please leave a comment below or feel free to email me at [email protected]. I do have an email list if you would like to get notifications of new products, blog posts, or TPT sales. And as always...have fun! Ashley Grapes (Science with Grapes) |