CEADI PREPARA | 4° ano Matemática | Contagem de uma sequência | 2º bimestre | Prof. Alyson Oliveira

🟡 This video follows the Editorial Line: CEADI PREPARES To access other videos and ready-made, free lesson plans: https://sites.google.com/edu.anapolis... 📚 Pedagogical Tip | Tutorial with examples | Curriculum Matrix | Curriculum Outline | Cross-cutting themes | BNCC Skills | Digital Education 🗓️ Year/Grade: 4th Grade of Elementary School *📘 Curriculum Component: Mathematics * 📌 Theme / Object of Knowledge:* Counting a sequence *OBMEPMirim 🎯 *Summary of Content / Activities 🔎 1. What is a Sequence and what is its "Secret"? Show students that a mathematical sequence is like an organized line where each element occupies a fixed position and follows an invisible rule called a pattern. Numerical Sequences: The numbers are constantly "jumping." Example for the board: 2, 5, 8, 11, 14... Investigation with the class: What is the secret of this sequence? To go from 2 to 5, we add 3. From 5 to 8, we add 3 again. The "secret" is adding 3. Figurative (Visual) Sequences: Repetition of shapes or objects in cycles. Example for the board: 🟡 🟥 🔺 🟡 🟥 🔺 🟡 ... Investigation with the class: The repeating block has 3 figures (circle, square, triangle). If the cycle restarts, the next figure will be the 🟥 (square). 🛠️ 2. Reasoning Strategies in the Style of OBMEP for Young Students To solve Olympic sequence problems, teach students to use two fundamental strategies: Strategy A: Finding the Constant Difference If the sequence is numerical and is increasing or decreasing, subtract one term from its neighbor to find the size of the "jump". If the sequence is: 120, 145, 170, 195... Calculation: 145 - 120 = 25. The jump is +25. Therefore, the next number will be 195 + 25 = 220. Strategy B: Division by Cycles (For very distant positions) In questions like: "What will be the 50th figure in the sequence?", drawing everything takes a lot of time. Teach the logic of groups. If the sequence repeats a block of 4 figures (e.g., 🌟 🎈 🚗 🍫), all positions that are multiples of 4 (4, 8, 12, 16...) will end with the last figure of the block (🍫). 🎮 Practical Activities in the Style of OBMEP Mirim (Brazilian Mathematical Olympiad for Juniors) Activity 1: Discover the Next Number (Numerical Regularities) Copy the sequences in your notebook, discover the "secret" of each one, and complete with the next two numbers: 🎰 Sequence A: $12, 19, 26, 33, 40, \_____\____\____ \____\____\____ The Secret: Add 7 (+7). Answer Key: 47 and 54. 📉 Sequence B: 98, 89, 80, 71, 62, \_\_, _\_\ The Secret: Subtract 9 (-9). Answer Key: 53 and 44. 🚀 Sequence C (Challenge): 1, 2, 4, 8, 16, __, __ The Secret: Multiply by 2 (double the previous number). Answer Key: 32 and 64. Activity 2: The Olympic Flashing Light Problem Ask students to copy and solve the problem below, practicing the logic of repetition: Statement: A panel of lights flashes always following the same color order: Green, Green, Yellow, Blue, Red. After Red, the cycle restarts from Green. A) How many lights form a complete repeating cycle? Answer: 5 lights (two green, one yellow, one blue, and one red). B) If the panel flashes 23 times following this exact pattern, what will be the color of the 23rd light to flash? Explain your reasoning. Expected student reasoning: Each complete group has 5 lights. 5 x 4 = 20 lights (4 full groups). Light number 20 is the last one in the group (Red). Now I count the rest: the 21st is Green, the 22nd is Green, and the 23rd will be Yellow. Answer: Yellow. ---- ➡️This content was produced by the Municipality of Anápolis, SEMED - Municipal Department of Education, CEADI – Municipal Center for Distance Learning of Anápolis. 🤝Objective: To connect students, teachers, and families in building a public, innovative, and quality education. 📚 For more lessons, tips, and learning paths, subscribe to the channel, activate the bell 🔔 and follow our content! ✨ Also visit our website: 👍https://sites.google.com/edu.anapolis... 🎯 Keywords: free video lessons, school reinforcement, elementary education, BNCC (National Common Core Curriculum), innovative education, hybrid teaching, teacher training, quality public education, Continuing Education.