I am now scanning the Wikipedia article on Chagas disease, taking in the structure and main sections. I am seeing that it covers a lot of ground—epidemiology, life cycle, diagnosis, treatment, prevention, history, and public health implications. The core subject is clearly a parasitic disease caused by *Trypanosoma cruzi* and transmitted primarily by triatomine bugs. I am noticing the article uses technical language but also includes accessible details like symptoms, transmission routes, and historical context. I am forming an initial idea for the lesson title: something that captures both the scientific nature and global impact of the disease. "Understanding Chagas Disease: A Global Parasitic Infection" feels right—it’s clear, comprehensive, and emphasizes the worldwide reach mentioned in the article, including non-endemic regions like the U.S. and Europe. For reading level, I am considering the vocabulary and complexity. While there are terms like "kinetoplast DNA" and "dilated cardiomyopathy," the overall structure is explanatory with clear sections. The target audience should be able to handle intermediate science—students aged 11–16 (KS3-KS4) can grasp cause-and-effect relationships, medical terminology with context, and real-world implications. I am deciding on KS3-KS4 as the appropriate level. Now I am moving to formulate learning objectives. I am seeing that the article dedicates significant space to how the parasite enters the body—via bites, blood transfusions, contaminated food/drinks, etc.—so I know this is a key theme. I am creating an objective around transmission methods because it’s central and requires understanding of vector biology and public health risks. The life cycle of *T. cruzi* is detailed in the "Life cycle and transmission" section, explaining how trypomastigotes enter the host, replicate as amastigotes, and burst out to infect new tissues. This is a core biological process, so I am deciding to make it a standalone objective about understanding the parasite’s life cycle. I am noticing repeated emphasis on diagnosis—microscopy, PCR, serological tests—and how these differ based on infection phase (acute vs. chronic). The article stresses that early detection is crucial for treatment efficacy, so I am adding an objective focused on diagnostic methods and their importance in public health. Treatment options are clearly outlined: benznidazole and nifurtimox with side effects, limited effectiveness over time, and the lack of a vaccine. This is leading me to think about both the medical response and the public health challenges, so I am formulating an objective around treatment and prevention strategies. Finally, I am seeing strong data on prevalence—6.5 million cases in 2019, transmission through migration, organ transplants, and the global burden of disability-adjusted life years. This is leading me to conclude that students should understand not just the biology but also the human impact, so I am adding an objective about the global impact of Chagas disease. Now I am building key concepts based on these objectives. For the first concept—how bugs transmit the parasite—I am pulling information from the "Transmission" and "Life cycle" sections. The article explains that trypomastigotes are shed in feces after bites, and this is how infection occurs. I am thinking of an analogy to make it intuitive: comparing the bug bite to a dirty needle injecting liquid into the skin feels strong because both introduce something invisible that can cause harm. For the second concept—acute vs. chronic stages—I am focusing on the "Signs and symptoms" section, which clearly distinguishes early asymptomatic infection from later organ damage. I am seeing that most people are symptom-free in the acute phase but face long-term complications like heart disease. To simplify this, I am using the analogy of a virus that hides until years later—something students can relate to from personal experience with colds or flu. For the third concept—diagnosis—I am comparing the different methods: microscopy for active infection, PCR for sensitivity in early stages, and serological tests for chronic disease. The article notes that blood concentration drops over time, so I am thinking of a car analogy: if you miss the driver (parasite), you need to find clues left behind like oil or rust—this mirrors antibody persistence after infection clears. For the fourth concept—treatment challenges—I am reading about drug efficacy decreasing with time and high dropout rates due to side effects. The article mentions benznidazole causes skin rashes and digestive issues, while nifurtimox affects nerves. I am comparing this to treating an illness that gets worse over time despite medication, like a persistent flu—that makes the need for early treatment intuitive. For the fifth concept—global spread via migration—I am focusing on the "Non-endemic countries" section, which discusses U.S., European, and Asian cases linked to immigrants from Latin America. I am thinking of an analogy about bringing an invisible virus from another country, like a new strain of flu arriving through travel—this highlights how global movement shapes disease spread. Now I am designing the quiz questions. For the first question on transmission, I am using the article’s emphasis on kissing bugs and feces to create a plausible distractor (like mosquitoes) that students might confuse with malaria or dengue. The correct answer must clearly reflect the vector-borne nature of Chagas. For the second question on chronic disease diagnosis, I am pulling from the "Diagnosis" section which states antibodies persist in the blood after infection clears. I am crafting distractors that sound reasonable but are wrong—like detecting live parasites (which aren’t found in chronic stages) or using x-rays (not mentioned as diagnostic tools). For the third question on treatment, I am focusing on the article’s point that drugs don’t reverse heart damage. The correct answer must reflect this limitation, while distractors suggest false benefits like curing long-term complications. For the fourth question on oral transmission, I am using the "Transmission" section which explains that heating kills parasites but not eggs in food. I am including a distractor about cooked meat to test understanding of parasite survival in food and drink. Finally, I am working on the engagement hook and thought experiment. For the hook, I am choosing a relatable scenario: someone unknowingly infected during travel or organ transplant. This mirrors real-world concerns mentioned in the article (e.g., blood transfusions) and sparks curiosity about silent infection. For the thought experiment, I am imagining a public health worker designing a prevention campaign in a non-endemic city. I am drawing from the "Prevention" section on bed nets, insecticides, and screening programs. I am asking students to apply knowledge of transmission routes—like contaminated food or blood—to craft effective strategies. This promotes critical thinking by connecting science to real-world action. I am now satisfied that each part of the JSON aligns with the article, uses accessible language, and builds a coherent narrative for student understanding.