To calculate volume in liters, measure the dimensions of the object in centimeters, calculate the volume in cubic centimeters, and convert the volume to liters. The project requires a metric ruler. A calculator reduces the time to complete the calculations and the chances of a math error.

**Measure the object**Place the zero mark of a metric ruler on one edge of the object, and read the measurement. The major divisions are each 1 centimeter apart, and the minor divisions are 0.1 centimeter apart. If using a millimeter ruler, labeled 'mm' before the first major division, the major divisions are labeled in increments of 10 centimeters. Convert the measurement to centimeters before proceeding.

**Calculate volume in cubic centimeters**Use the measurements to determine volume. Use the appropriate formula for the shape of the object. For a rectangular prism, area is the product of the length, width and height. For a cylinder, multiply the square of the radius by pi by the height. Use a pocket calculator to save time when multiplying decimal numbers.

**Convert cubic centimeters to liters**There are 1,000 cubic centimeters in a liter. Multiply the volume of the object in cubic centimeters by the conversion factor 1 liter/1000 cubic centimeters. Label the final answer with the unit liters.