The purpose of this lesson is for students to add and subtract within 20. Students measure lengths of objects and represent measurement data in line plots and answer questions about the data.
In this lesson, students continue to practice fluency with addition and subtraction within 20 with an emphasis on knowing from memory single-digit addition facts. Students revisit line plots, which they worked with in a previous unit. They measure the length of objects and use measurement data to create line plots.
- Action and Expression
- Fluently add and subtract within 20.
- Measure lengths in centimeters.
- Represent measurement data in a line plot.
- Hagamos diagramas de puntos, y sumemos y restemos medidas de longitud.
- Each students needs an unsharpened pencil.
- The activity works best if it is likely that students will have a range of pencil lengths between and among groups. If necessary, sharpen pencils to different lengths and distribute them randomly to students.