What We Know

Measurement involves several components:

• Students must understand the concept, the need for measurement and the meaning of the number used as the "measurement" of an object.
• Students must be able to identify what attributes can be measured and can be assigned a numerical value.
• Students must know what tools, units and techniques can be used to assign this value.

Research suggests that American schools are not doing a good job teaching measurement. The performance of students from the United States does not compare favorably with the performance of students in other countries worldwide. The findings from the 1995 administration of the Third International Mathematics and Science study (TIMSS) show that American students in grade eight performed significantly below the international mean in measurement (National Center for Education Statistics, 2000). Studies have also shown that students in middle school often confuse perimeter and area in problem solving (Lindquist & Kouba, 1989; Woodward & Byrd, 1983). On National Assessment of Educational Press (NAEP) only 42% of fourth graders and 66% of eighth graders could draw a figure with the correct area (Dossey et. al, 1993).

What insights can research provide into how teachers can effectively teach measurement to students? Providing opportunities for hands-on practice is one way. Research shows that students need hands-on practice using non-standard and standard units of measurement (Hiebert, 1984).

In later grades, as students are introduced to more formulas than hands-on measurements, estimation has shown promise. The best way to develop this skill is to have students estimate and then use formulas (Bright, 1976). This may help understanding and prevent confusion, such as that between area and perimeter described above (Bright & Hoeffner, 1993). In addition, students should be taught that measurements such as length, area, distance and time are approximations; they can be made more accurate by using a smaller unit, but they are always approximations.

Research has suggested that the order in which teachers introduce measurement topics may not be as important as how teachers introduce these topics. It implies that among length, area and volume, none is a prerequisite for the others (Hart, 1984). Instruction in measurement should focus on both customary and metric systems. Many students lack skills in estimation in metric measurements particularly (Bright & Hoeffner, 1993), and these can be developed through instruction.