Students are asked to guess and then measure lengths of objects using a 12-inch ruler and to record two measurements on the "I Can Measure Inches" sheet, providing direct practice with estimating and measuring in inches. Students measure prepared straw pieces (1–6 inches), learn to line up objects at 0 on the ruler, identify inch marks and half-inch marks, and round measurements to the nearest inch. Students are shown a meter stick and a cloth tape measure that includes centimeter markings, indicating exposure to metric tools.

Activity 1 has students use a 12-inch ruler, identify that 12 inches = 1 foot, and measure or build objects of specified lengths in feet (1 ft, 2 ft, 3 ft, 4 ft), including procedures for measuring longer than one foot. Activity 2 has students estimate lengths by circling whether an object is best measured in inches or feet and explain why they chose inches or feet. The Skills list and prompting ask students to select and use appropriate measuring tools (rulers, yardsticks, meter sticks, measuring tapes).

Students measure an index card in centimeters and are asked to guess how many inches each side measures before checking with an inch measurement, which practices making and checking estimates in inches and centimeters. Students use a meter stick to locate and compare a meter (100 cm) and are asked to find several household objects that are "about a meter long," practicing estimation with meters. Students cut and sort picture cards into groups for items better measured in centimeters versus meters, practicing selection of appropriate metric units. The meter stick discussion also has students compare a meter to a yard (36 inches), giving comparative understanding of metric and customary units.

The lesson's Skills list explicitly includes "Estimate lengths using units of inches, feet, centimeters, and meters." In Activity 2 students guess their height in inches and centimeters and then measure to compare guesses to actual measures. In Activity 3 students search for objects that are "about an inch, about a foot, about a centimeter, and about a meter," using a ruler and meter stick to identify and record approximate lengths.

Students cut and sort measurement terms into Customary (inch, foot, yard) and Metric (centimeter, meter) categories, showing recognition of the units. Students roll a die and draw straight lines that are a specified number of inches, using a ruler to create lines of given inch lengths. Students use a ruler and a geoboard to construct shapes with specified centimeter side lengths (e.g., squares with 9 cm and 15 cm sides, a 6 cm by 12 cm rectangle, and a triangle with two 18 cm sides and a 25 cm third side).

Students are asked to select and use measuring tools (ruler, meter stick, metal and cloth tape measures) and to identify inches, feet, centimeters, and meters on those tools. Students lay out tape measures, compare which tool measures longest, and decide which tool is best for measuring specific objects (can, wall, table, rug, ribbon, child). Students complete a cut-and-paste activity matching measuring tools to real scenarios, and label who would use a ruler, tape measure, or meter stick for tasks.

Students are asked to estimate the length of a pencil in centimeters and inches and then measure it using a ruler (Activity 1). The Kitchen Measurement activity has students measure several kitchen items and record lengths in inches and centimeters and compute differences. In Activity 2 students cut ribbon in given numbers of inches, estimate the lengths of two randomly chosen pieces, then measure and write subtraction sentences showing the difference in inches.

Students are prompted in Activity 1 to pick three gummy worms, place them shortest to longest, and estimate their lengths in centimeters. In Activity 2 students measure seven gummy worms in centimeters before and after stretching and record those measurements with "cm" labeled. In Activity 4 students measure several drawn lines in inches with a ruler and then plot those inch measurements on a line plot.

Students are prompted to show with their hands and body the approximate lengths of a centimeter, an inch, a foot, and a meter. Students are asked to find objects that match specified lengths labeled in centimeters, inches, feet, and meters (for example, find an object in the room that is 6 centimeters or 1 meter) and to record those measurements using the correct unit abbreviations. Planning and data pages instruct students to use all four units and to select appropriate tools (rulers, yardsticks, meter sticks, measuring tapes) to measure objects to the nearest whole unit.

The Skills list explicitly includes "Estimate lengths using inches, feet, centimeters, and meters." In Activity 1, students identify inch, foot, centimeter, and meter, use their bodies to show lengths, and use a ruler/meter stick to find objects that match given lengths (e.g., 2 inches, 10 centimeters, 1 foot, 9 inches, 1 meter, and items on the second page including 2 feet and 2 meters). In Activity 2, students decide which unit is appropriate for different objects (rug: inches vs feet; centimeters vs meters), compare 60 inches vs 60 feet, play a unit-appropriateness game, and circle the most sensible centimeter- or meter-based length for pictured objects on the "Review: Which Length?" sheet.