Calculating Area of Rectangles Level: Primary --- Content: Math |
Ms. Ramon’s third grade class has been learning multiplication facts and how to use them to solve problems. Today they are working on finding the size of a two-dimensional flat surface. Ms. Ramon begins with several hands-on activities that are easy for them to visualize and remember. First, she marks off squares and rectangles on the floor with tape and has the children arrange 1 foot (or 1 meter) carpet squares inside the space and count the number of squares to come up with a measurement. The students compare the number of squares that fit inside smaller and larger shapes. Next, she gives each student a piece of paper with a square or rectangle marked off on it. She also gives them a bag of square crackers and they repeat the carpet activity. They label the size of each shape as number of square crackers or number square feet (or meters). Next Ms. Ramon uses her laptop and a projector to show the students how to do a similar activity on the computer. Using Cacoo, a collaborative diagramming tool, she draws a large rectangle on the screen and drags enough squares on top of the rectangle to fill it. There are 2 rows of 3 squares. The students then count the squares and label the area of this as 6 square Cacoos, an invented unit of measurement. She then uses the group function to connect the 3 squares in a row so that they can be moved as a unit. They then discuss that the rows are equal and that 2 rows of 3 squares equals 6. She then shows them several ways to write this as a formula 3 + 3 = 6 or 3 x 2 = 6. She shows them that if they know the number of squares in a row and the number of rows, they can calculate the area without filling in all the squares. Finally, she has the students work in pairs using Cacoo, each on their own laptop. One student draws a rectangle on the screen and the other drags squares into the rectangle and either counts, adds, or multiplies to calculate the area. The next day, Ms. Ramon uses a multiplication manipulative to review the concepts of the previous day. The manipulative shows a rectangle superimposed on a grid of small squares. It shows the various ways that the area of the rectangle can be calculated. The students can change the dimensions of the rectangle easily to generate new examples. Ms. Ramon asks the students who are having difficulty with the concept of area to study a learning object on the Internet. The learning object is called found at a site called TV411, It provides a short digital lesson with content, practice problems, and assessments. When students understand the area concept, but need to build fluency with multiplication facts, she gives them time to do a skill building exercise. The exercise presents students with 10 multiplication problems and gives them feedback on their accuracy and the time required to solve the problems. The goal is to complete 10 problems in under a minute. They can print out their best time and hand it in as a homework grade. Finally, Ms. Ramon wants to assess how well the students understand the concept of area and their multiplication facts. She uses an online assessment tool called Quia to create a quiz. The tool allows her to create multiple choice, matching, short answer and many other types of questions. Once the students take the quiz, their scores are saved so that Ms. Ramon can review them. Tools used in this scenario:
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