E2. Measurement
Specific Expectations
Attributes
- identifying measurable attributes of an object:
- measurable attributes of two-dimensional shapes:
- length, height, width
- angles
- perimeter
- area
- measurable attributes of three-dimensional objects:
- length, height, width, depth
- angles
- surface area
- capacity
- mass
- Every shape or object has several attributes that can be compared. The same shape or object can be described and compared using different attributes.
- There are particular words that describe commonly measured attributes:
- length is the distance from one point to the other and can be measured in any direction;
- area is the amount of surface an object has;
- mass is how heavy an object is;
- capacity is the amount an object holds;
- angle is the amount of turn between one line and another.
Have students look at relevant real-life items and describe their measurable attributes. For example, give them a cup and an analog clock. They might notice that both objects have a mass; that the cup has capacity (can be filled), but the clock does not; or that they both have lengths, including height, width, and distance around. Students might also notice that the hands on the face of an analog clock form angles.
E2.2
compare several everyday objects and order them according to length, area, mass, and capacity
- comparing objects:
- directly comparing one object to another:
- indirectly comparing two objects using a third object:
- length: using string to compare the lengths of the two objects
- area: using square tiles to cover the surfaces of the two objects
- mass: using a balance to compare the mass of each object to a third object
- capacity: pouring the contents of both containers into a third container, one at a time (emptying the third container in between)
- Objects can be compared and ordered according to whether they have more or less of an attribute. Comparing the same objects by different attributes may produce different ordering.
- There are specific words and phrases that help describe and compare attributes:
- more, less, smaller, and bigger often only describe general comparisons unless a specific attribute is included (bigger area; smaller capacity);
- tall, short, wide, narrow, long, and distance are all associated with length;
- adding the suffix “-er” or “-est” typically creates a comparative term (e.g., heavier, lighter, heaviest, lightest).
- Objects can be directly compared by matching, covering, or filling one object with the other to determine which has more length, mass, area, or capacity.
- When a direct comparison cannot be easily made, a third object can serve as a “go-between” tool to make an indirect comparison. For example, a string can be used to compare the lengths of two objects that are not easily brought together, or a third container can be used to determine which of two containers holds more water. Indirect comparisons require using the transitivity principle and the conservation principle.
Have students play “Which Is More?”, where they directly compare two objects based on a measurable attribute. For example, to find which object is longer, they could place one object beside the other. To find which object has a greater area, they could lay one surface on top of another. To find which object has a greater mass, they could hold an object in each hand and decide which feels heavier. To find which object has the greater capacity, they could pour the contents of one container into the other to see which holds more. Ask them to describe the measurable attribute they compared and share the strategies they used to make the comparison.
Have students use a tool to solve problems that involve comparing two objects based on a measurable attribute. For example, have them use string to determine whether a desk can fit through a doorway, square tiles to determine which of the two areas is greater, a balance and a third object to compare the masses of two objects, or a cup and water or sand to compare the capacities of two containers.
Have students select three or more items. Have them predict the order from least to greatest (or vice versa) according to a measurable attribute. Then have them test out their prediction (visualize, verbalize, verify). Then have them predict the order of the same objects using a different attribute, and guide them in noticing that the order may change. Provide them with opportunities to prove or disprove their predictions and share their insights with the class.
Time
E2.3
read the date on a calendar, and use a calendar to identify days, weeks, months, holidays, and seasons
- contexts for using a calendar:
- recording special celebrations (e.g., personal or cultural events, holidays)
- recording upcoming events (e.g., school assemblies, pizza day)
- recording appointments (e.g., doctor, dentist, haircut)
- tracking data (e.g., type of weather, temperatures)
- Time is an abstract concept that cannot be seen or felt. The passing of time can be measured by counting things that repeat. The passing of a day, for example, is marked by the rising and setting of the Sun.
- Calendars keep track of days, weeks, months, and years, as well as holidays and seasons.
- There are other kinds of calendars, such as lunar, solar, agricultural, ecological, and personal calendars, that keep track of personal, social, and religious events.
- Calendars enable people to communicate a date to others.
Make a class calendar, and discuss as a class which key dates to include. Ensure that all students are encouraged to share personal and culturally relevant events from their diverse experiences and backgrounds. Depending on their suggestions, some dates may need to be indicated on the calendar as a range of days, specific weeks, or months.