Order three things without tools. For example, we can compare lengths or heights of physical objects or figures (such as lines). We could also compare by weight: hamster, dog, elephant. Or by temperature: malt, milk, hot chocolate. Keep in mind that we’re restricting ourselves to things we’ll learn how to measure later. We’ll measure lengths and heights with a ruler, mass with a scale, and temperature with a thermometer.
Ordering by length by Khan Academy
Conclude by leading this investigation:
No Three in a Line
1.MD.A.1: Order three objects by length; compare the lengths of two objects indirectly by using a third object.