Chemistry is the study of matter and the changes that can be made to it. Chemistry involves almost anything we see, touch, smell, taste and hear, so it is a very expansive science. Most people think of liquids in beakers and labs when they think about chemistry, but chemistry is truly all around us. Subjects that deal with chemistry include acids and bases, crystals, chemical and physical change, states of matter and the human body.
Try a variety of experiments based on the subject you are teaching to your second-grade class. Describe what physical and chemical changes are and show these types of changes to your class by dissolving sugar in water and growing crystals afterwards. Explain chemical reactions with a simple acid-base reaction; mix vinegar with baking soda and watch the results, or mix lemon juice with baking soda in a cup and use it to clean desks or countertops. Show states of matter by putting colored water into an ice cube tray and making ice cubes; then put the solid ice cubes in direct sunlight and see the solid become liquid. Ask your students to bring a label from a food item at home and discuss what nutrients and chemicals are in food.
Integrate science experiments and subjects in other classroom activities. For example, have your students draw a diagram of one of the experiments you performed. Draw or paint the different states of matter. Write a rap or song that involves vocabulary words or actions from experiments. Divide your class into teams and play a trivia game to review facts learned through the experiments. Have a group or individual read a report or give a presentation about a chemistry fact.
When doing any experiment, consider safety and the activity's appropriateness. Always review safety procedures before doing any experiment. Use safety goggles and gloves when necessary. Do not use dangerous substances. Stick to household items such as lemons and baking soda because these items are typically found in your students' homes and they are less likely to injure themselves with such products. Think of the purpose for each activity; you want the experiments to be fun, but they must also serve an educational purpose.