I start this lesson by reviewing tally marks. We start by watching this video about tally marks.
I like to start this lesson with this video because it’s a nice review of using tally marks. A concept, that for some students, can be difficult. Due to the complexity of students remembering to make a slash mark for the fifth tally mark, I wanted to make sure to incorporate this review into this activating strategy to allow students more exposure to tally marks.
This activity connect to MD.C4 by demonstrating another way to represent and organize data. The use of tally marks represents an easy way to show data in increments of 5; thus making it easy to count.
After watching the video, we review the process of gathering information. I tell them that in this lesson, they will be getting some Goldfish crackers (I buy the box that has individual bags of goldfish in different colors) that we will be sorting and graphing. I tell them that we are making a bar graph by coloring in correct number for each color of goldfish.
Many times, when students are having difficulty with coloring in the correct number of cells in a bar graph, it helps them to have a concrete model. This activity helps those students that are having difficulty coloring in the correct number of cells because I encourage students to actually place one goldfish in each cell before coloring in their graphing sheet. In the MD.C.4 standard, the most difficult part of the standard is for students to discern how many more or less in one category than another. By allowing them to put their goldfish on the graph before coloring, it helps to move the graph from a concrete to an abstract model.
They are also modeling with math (MP4) by placing individual goldfish in each cell before coloring in their graph and answering the questions.
I hand out the bags of goldfish and instruct students to open their bag and sort their goldfish by color. I then have students begin to count their goldfish or place them on the graph according to color.
Once all students are finished, we go through the questions at the bottom of the Goldfish graphing worksheet.docx. I then turn them loose to answer the questions about their graph.
In this video, a student is explaining how she is sorting her goldfish on her graph. This video demonstrates the students using models to graph (MP4). After taking the video, I discussed with the class the importance of making sure to work precisely so that there is only one goldfish per cell on their graph the way this student does (MP6).
To close out the lesson, I have each student compare their findings with a partner. This enables them participate in mathematical conversations (MP3) with each other and compare the amount and colors of fish that they both have. Each student will have differing amounts of colored goldfish crackers, so this activity will allow them to explain why one color had more or less than another color.