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How Long?


Alignments to Content Standards: 1.MD.A.2

Task

You will need various items to measure, a large set of cubes such as unifix or snap cubes, and a recording sheet with 4 sections. In each section would be the words: _______ cubes long with enough space for a small drawing. The students work in pairs. They choose an item to measure. First they line up the cubes along the longest side of the item. They count and record the number on the first line in the first section. They draw a picture of the item they measured. They continue same routine 3 more times with different items. Photo_1_a21a55d4ec8505dab66718b19c30d582Photo_2_295d02fb023abaeec8c3b7518b2bac58Photo_3_230b02360ef363ac5ee7d1118663e4a6

IM Commentary

* The students may need to first be shown how to measure length correctly by starting at one end and going to the other end.

* If the students are not facile with number formation, then a number chart can be used for reference when they need to record the number.

* Working in pairs supplies support to those students who may be struggling with number names or writing numbers. The main focus is to do the measuring the object.

* After this activity has established the routine of measuring, then as a variation, different manipulatives, such as chip counters, chain links, cuisenaire rods, or bear counters can be used to measure the items. You could also measure one item only using 4 different manipulatives.

* Two different blackline masters are attached. The both achieve the same math objectives, however one has more written language on it so teachers can decide which is appropriate for their students.

The Standards for Mathematical Practice focus on the nature of the learning experiences by attending to the thinking processes and habits of mind that students need to develop in order to attain a deep and flexible understanding of mathematics. Certain tasks lend themselves to the demonstration of specific practices by students. The practices that are observable during exploration of a task depend on how instruction unfolds in the classroom. While it is possible that tasks may be connected to several practices, only one practice connection will be discussed in depth. Possible secondary practice connections may be discussed but not in the same degree of detail.

This particular helps illustrate Mathematical Practice Standard 5, Use appropriate tools strategically. During this exploration, first graders investigate the attribute of length by using a common measurement tool such as snap or unifix cubes to directly measure objects in the classroom. In this case, students lay the cubes end-to-end and count them to measure a length. As students become proficient in this practice, they will be able to consider a tool’s usefulness and consider its strengths and limitations, as well as know how to use it appropriately. Since this may be a new experience for students, they may initially leave gaps between cubes or overlap cubes. The necessity of aligning the cubes accurately can be reinforced throughout this activity. After students feel comfortable with measuring with the cubes, they can select another common tool to use to measure the same objects. A conversation about which measuring tool may be more useful would support the development of MP.5 Further exploration with multiple measuring tools will result in differences in lengths. This observation provides an opportunity for students to explain why there are differences and how does that impact your choice of tools (MP.3).

Solution

The students should become familiar with the word, “long”, and its reference to length.

The students should become aware that an item can have different lengths depending on what you use as a measuring tool.