Tuesday, February 12, 2013

Prime and Composite lesson plan

Hello again!  Today, I'm sharing another lesson plan that I've written for my first "core curricular" class in Grad school.  I have adapted a typical math lesson on prime and composite numbers to include multiple modalities to suit varied learning styles.  Instead of creating a Google doc, I decided to just paste it into my blog post this time for easier access. 

My independent practice sheet was a freebie from Ms. Ashley's Resource Room  Thanks so much for sharing! 

Prime and Composite lesson plan

Content area:  Math          Grade level:  3 – 4          Date:  Winter 2013

Students will demonstrate understanding of, and classify prime and composite numbers with 80 percent accuracy. 

Standard Addressed:
CCSS.Math.Content.4.OA.B.4 Find all factor pairs for a whole number in the range 1–100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole number in the range 1–100 is a multiple of a given one-digit number. Determine whether a given whole number in the range 1–100 is prime or composite.

The goal of this lesson is to demonstrate the abstract concept of prime and composite numbers with varying modalities.  In addition to the teacher’s explanation and mental modeling, students will view and interact with the graphic organizer as well as manipulatives. These added visual and kinesthetic modalities, along with guided interaction, support English learners, as well as other learners with varied learning styles.  This lesson assumes that students are already fluent with many multiplication facts, and understand the concept of dividing a number into its subgroups of factors. 

Introduction & Guided Practice:
The teacher begins by passing out bags of two-color counters to each table, and asks students to model the number 16, as if they had just completed a multiplication problem.  Volunteers explain how they have grouped the counters, either in arrays or small clusters.  Then, all counters are returned to the bag, and the teacher asks that students model the number five.  The teacher encourages discussion among group members regarding how the counters will be grouped.  After students struggle for a few minutes with this dilemma, the teacher calls students’ attention to the graphic organizer that s/he has placed on the board or document camera (see below).  The chart has two columns for prime and composite respectively.  “What differences did you find when grouping five and sixteen?” asks the teacher, as s/he copies students’ replies on a list displayed for the class.  When the students voice the fact that five can’t be divided evenly, it is drawn on the Prime side of the chart, displaying 5 and 1 as its only factors.  Students then volunteer possible groupings for 16, which include 4 and 4, 8 and 2, and 16 and 1, and are drawn on the composite side of the chart.  Students then pick a number at random between 1 and 12, and the class decides together, using two-color counters whether it can be divided evenly.  Then, a student volunteers to draw its factors on the appropriate side of the chart.  This is repeated once again to provide additional guided practice.  The teacher asks students what important words they have used when discussing this process with group members, and adds any to the list which students have omitted.  These can include prime, composite, factor, multiple, etc.  This provides English learners with practive using the academic vocabulary surrounding this concept. 

Independent Practice:
   The teacher then distributes the independent practice sheet (see Here), which also contains a completed concept map at the top.  There are five or six exercises on this sheet which involve deciding whether numbers are prime or composite, and listing the factors of composite numbers.  Students are permitted to ask fellow table group members for clarification if they have questions.  They are also permitted to model with the counters if needed.  The teacher circulates to answer questions and monitor student activity.  S/he may need to provide additional scaffolding to some students. 

Students will return to large-group setting after a predetermined time, and offer any conclusions or discoveries that occurred to them while practicing.  One or two volunteers may add another number or two to the graphic organizer.  The teacher collects the independent practice sheets, which do not need to be finished. 

Assessment & Extension:
The independent practice sheet will serve as a formative assessment to determine which students have successfully classified the attempted numbers with 80 % accuracy.  This concept, as with most others, will then be incorporated into future authentic problem-solving activities. It can also serve as a center activity for those who have met the objective, and a guided math group activity for those who have not.   Additional practice can be gained from textbook exercises assigned for homework for those comfortable with the concept. 



  1. Wow, this looks great!! I'm so happy you that you were able to use that worksheet! Nice lesson =)

    The Resource Room Teacher

  2. Thank you for posting this on Math Monday Blog Hop! Hope to see you there again!