Students investigate how exercise changes the heart, lungs, and muscles through movement, observation, and discussion. They build science understanding by measuring pulse and breathing, using diagrams and models, and showing what they learn about the different body systems. Working with classmates and the gym teacher, they collect evidence, reflect in journals, and revise their ideas to answer the essential question. The experience helps students connect body science to healthy choices and share practical findings with families and peers at the Heartbeat Expo.

Students investigate how exercise changes the body by identifying the basic jobs and main parts of the heart, lungs, and muscles using models, diagrams, and movement experiences. They learn to measure pulse and breathing before and after different exercises, record observations in journals and charts, and look for simple patterns in their data. Working with classmates and the gym teacher, they ask questions, share roles, compare results, and revise drawings and explanations to clearly communicate their scientific thinking. By the end of the project, students create and present visual products that explain how movement affects the body and encourage healthy activity in their community.

Students will create daily reflection journal entries with simple drawings, labels, and number records showing pulse and breathing before and after movement. Throughout the project, they will also make practice charts, labeled body system diagrams. By the end, each student will complete a visual poster or drawing explaining how exercise affects the heart, lungs, and muscles, using evidence from their observations. As a class, students will produce a large collaborative poster with labeled drawings and student-made charts to present during the Heartbeat Expo.

Begin with a “Heart Beat Adventure” scavenger hunt where students rotate to find clues about the heart, lungs, and muscles using pictures, simple models, and movement prompts. After the final clue, the class joins the gym teacher for a short movement challenge, then practices noticing and counting pulse and breaths before and after exercise. In pairs, students talk about what changed in their bodies and record one first observation in their reflection journals. Close with the essential question, “How does exercise affect our heart, lungs, and muscles?”

Host a Heartbeat Expo where students welcome families, the gym teacher, and another second grade class to rotate through stations. At each station, students demonstrate movement sequences, show how they measured pulse and breathing before and after exercise, and explain labeled drawings and class charts about the heart, lungs, and muscles. Display reflection journals, revised posters, and the large class poster so visitors can see how students’ observations changed over time. End with a short movement showcase and student Q&A so children practice clear speaking, listening, and sharing evidence from their investigations.