Grade 5 · Science · Lesson 3

Measurement Tools & Accuracy

Science depends on careful measurement. Scientists use special tools to record length, mass, volume, time, and temperature. The international system (SI / metric) is the standard in every science lab — meters, grams, liters, milliliters, degrees Celsius — because the units scale by powers of ten. In US homes, kitchens, and gyms, customary units (inches, feet, pounds, cups, gallons, °F) appear right next to the metric ones on most household tools. A good scientist can read BOTH scales and always writes a unit beside every number.

What this lesson teaches

1Identify common science tools and what each one measures in both metric (SI) and US customary units
2Read scales on rulers (cm and inches), thermometers (°C and °F), and graduated cylinders (mL)
3Write measurements with the correct unit, using metric for science and customary when working with everyday US objects
4Explain why accurate measurement, repeated trials, and reading the meniscus make results trustworthy

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