Jamal’s investigation plan shows this question: “What happens when I mix baking soda with lemon juice?” Materials: baking soda, lemon juice, clear cup, teaspoon, thermometer, tray, goggles. Procedure: (1) Pour 30 mL lemon juice into the cup and record the temperature. (2) Add 1 tsp baking soda and stir. (3) Record what you see and the temperature after 1 minute. Which part of Jamal’s plan best helps him measure a temperature change?
- Using a clear cup so the mixture is easy to see.
- Wearing goggles so the mixture does not splash into eyes.
- Using a thermometer and recording the temperature before and after mixing. (correct answer)
- Stirring the mixture so it mixes faster.
Explanation: This question tests 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically using appropriate tools to measure specific changes. When planning a mixing investigation, students need to select and use tools that measure the property they're investigating - for temperature change, this means using a thermometer and recording readings at specific times. For this question, Jamal wants to detect temperature change when mixing baking soda with lemon juice. Choice C is correct because it identifies both the tool (thermometer) and the procedure (recording temperature before and after) needed to measure temperature change quantitatively. This shows the student understands that measuring change requires taking readings at multiple time points with appropriate instruments. Choice B represents a safety measure (goggles) which is important but doesn't help measure temperature change. This typically happens because elementary students may confuse general good practices with specific measurement needs. To help students: Match investigation questions to measurement tools using a chart - 'If you want to measure temperature → use thermometer,' 'If you want to measure volume → use measuring cup,' etc. Watch for: Students who include the right tools in materials but don't specify how to use them in the procedure to actually measure changes.