Materials:Twist, ruler, pattern blocks, small paper clip, paper and pencil
Ask students to identify measurements in the metric system that measure length. Have students explain why we need different-sized units. Introduce the concept of millimeters, if necessary.
Place a ruler under Twist so the students can see approximately five full centimeters. Take a snapshot of the five centimeters. Then lower Twist and focus in on one centimeter. Take a snapshot of the centimeter.
Open both snapshots and place the images side by side. Ask the students to determine the number of millimeters there are in a centimeter. Compare the two snapshots to help with the concept.
Place the paper clip under the Twist and ask the students to estimate the length. Have students predict if the paper clip will measure a full centimeter or part of a centimeter. Place the ruler beside the paper clip and focus the Twist so the students can read the measurement. Help students determine the length in millimeters.
Provide the students with several Pattern Blocks and a ruler. Have them measure the blocks in millimeters and record their measurements on the attached sheet. Have students share measurements with the class and model how they determined the measurement by using Twist to show the process. Repeat several times.
Use snapshots from students' measurements with Twist to document their estimation and measurement skills.
If students are ready, introduce the concepts related to writing measurements to the nearest tenth of a millimeter and have students practice with the aid of Twist.