Make a large Venn diagram to identify items that give off heat and light. Draw two large circles on your chalkboard or whiteboard that intersect in the middle. Label the far left side of your diagram, "heat," the middle, "both," and the far right side, "light." Ask your second-graders to identify items that give off heat or light or both. For example, the sun gives off both heat and light and should be placed in the middle of your diagram. Fire would also go in the middle. Continue placing items in each section of your diagram. Alternatively, provide your second-graders with a smaller copy of the diagram and ask them to write words or draw pictures to complete the picture. This can be used as an assessment tool after your unit is over.
Take your second-graders on a hunt for sources of heat and light. Give each student a piece of paper divided into two sections, one for heat and one for light. Walk around your classroom and ask your students to identify items that give off heat or light, such as the overhead lights or the heater vents. Take the activity throughout the school and outside to continue the lesson. As students find objects, ask them to draw pictures or write words in the appropriate column. If an item gives of heat and light, have your students include it in both columns.
Teach your second-graders about light by asking them to put on shadow plays. First, demonstrate how a shadow is formed when the classroom is darkened and only a single light is shining. Show your students how to make shadow figures by waving their hands in front of the light source. Divide your class into small groups and ask them to make up a shadow play. Have each group show its play to the rest of the class, pointing out how the light and shadows shift at various points throughout each play. Alternatively, take your students outside and have them put on plays using the sunlight and different parts of their bodies.
Divide your second-graders into groups of three or four students. Give each group a thermometer. Ask the groups to walk around the classroom and take the temperature of various areas, such as near the window or classroom door. Have the students record the temperature of each area. Gather back together as a class and discuss what objects and areas give off heat. Ask your students to use their records to determine what object or area in the classroom is the hottest. Expand the activity by having students take temperatures around the school as well.