Fourth grade students learned multi-step problems involving conversion of units of measure for a given attribute within the same system of measurement, metric or customary (for length, volume, capacity, weight, mass, and time). Students solved the problems by creating tables. They understood the relationship that smaller units of measure can be composed to equal a larger unit of measure, and that larger units of measure can be decomposed into smaller ones within the same system of measurement.
Students solved real-world problems that involved performing conversions between various units of measure with the same attribute. They created conversion tables and described the relationship between measurement units in both customary and metric systems. They also justified the relationship between customary or metric measurement units when converting between units of measure by using pictures, numbers, words, and symbols. Students often confused units of measure for capacity (liquid volume) with units of measure for weight (e.g., ounces instead of fluid ounces). They struggled with creating the inverse of a numerical expression e.g.- meters = km x 1000 and km = meters / 1000. Occasionally they had some difficulty picking the correct operation to use i.e. multiplication or division when converting from larger to smaller or smaller to larger unit.