Author: Mathew Needleman  Date Created: 8/9/2003 11:15:52 AM PST
Collections: Missing Pieces
Grade/Level: 1
Students: 20 students. 10 boys. 10 girls. 16 ELL students. 1 student mild autism.
Subject Area(s): Mathematics
Concept(s): Subtraction means taking objects away. One less than a number is the number that comes before it when counting.
State Academic Content Standard(s): CA- CCTC: CSTP's (Standards for the Teaching Profession) • Standard : Standard for Engaging and Supporting All Students in Learning Teachers build on students' prior knowledge, life experience, and interests to achieve learning goals for all students. Teachers use a variety of instructional strategies and resources that respond to students' diverse needs. Teachers facilitate challenging learning experiences for all students in environments that promote autonomy, interaction and choice. Teachers actively engage all students in problem solving and critical thinking within and across subject matter areas. Concepts and skills are taught in ways that encourage students to apply them in real-life contexts that make subject matter meaningful. Teachers assist all students to become self-directed learners who are able to demonstrate, articulate, and evaluate what they learn. • CSTP Key Element : Engaging students in problem solving, critical thinking and other activities that make subject matter meaningful.  Question: "How do I?" or "Why do I?" : engage all students in problem solving activities and encourage multiple approaches and solutions? CA- California K-12 Academic Content Standards • Subject : Mathematics • Grade : Grade One By the end of grade one, students understand and use the concept of ones and tens in the place value number system. Students add and subtract small numbers with ease. They measure with simple units and locate objects in space. They describe data and analyze and solve simple problems. • Area : Number Sense • Sub-Strand 1.0: Students understand and use numbers up to 100:  Standard 1.1 (Key Standard): Count, read, and write whole numbers to 100.
Objective(s): After guided practice counting backwards, students will be able to determine the number of objects left in a set when a particular number are taken away with ninety percent accuracy.
Prerequisite Background Skills/ Knowledge: Students should know their numbers and what they look like. A couple of my students need additional practice writing their numbers, they don't know which number is which.
Vocabulary/Language Skills: Subtraction: Student will come to see it through these activities as a loss (I had this many but lost this many).
Materials: Book: Ten, Nine, Eight by Molly Bang Television Laptop Appropriate technological connections Software Program Paper
Classroom Management: Discuss appropriate TV watching behavior. Model worksheet completion and circulate to provide help.
Models of Instruction: Direct Instruction
Procedure
Open: Read the story, "Ten, Nine, Eight" a counting backwards book by Molly Bang to students, allowing them to predict the number that comes next. Use this opportunity to assess students ability to count backwards and provide practice counting backwards after the completion of the book.
Input: On a separate day, present students with a collection of objects like toy cars and walk them through scenarios where some of the cars would be lost or drive off and have them tell you how many would remain. Provide much practice with this before attaching a name or symbol to the operation.
Guided Practice: When students are ready, begin to discuss the operation of taking items away from a set and put the name and symbol for subtraction to it. This part of the lesson will be presented on a television with a connection to a laptop. Continue as before but now have students assist you in writing a number sentence to go with the scenario. Number sentences will appear on the TV screen. Present students with a virtual collection of objects in a drawing program and as you present new scenarios, place electronic X's on those items that are being taken away from the set. Again have students assist you in writing number sentences and place these number sentences on the screen under the illustrated picture.
Independent Practice: Students will have their own papers on which to write number sentences to go with virtual illustrations. As an alternative allow students to draw pictures if they would prefer (e.g. five dogs with two crosses out and the number 3 written next to it). Present a few more scenarios but as students get good, present only a picture and ask them to make up a story to go with it.
Close: Discuss with students the meaning of subtraction as taking items away and have them share their comments on creating stories to go with number sentences.
Assessment/ Reflection
Assessment: Teacher will assess whether students are able to determine how many objects remain when a certain number are removed from a set with ninety percent accuracy. Teacher will examine both students' work on paper and their comments in class to assess the success of learning in this lesson.
Reflection: Students liked the hands on nature of this activity. While teaching, I realized that students would benefit from having some manipulatives that they could touch while they watched the virtual manipulation on screen and so I passed out cubes to students. Whereas other experiences with manipulatives have had mixed results, the mixture of real life manipulatives and the virtual manipulatives on the screen allowed most students to be able to use the manipulatives in front of them to help solve problems. Many students understood the concept and this was very rewarding to see. I still have some students who need remedial mathematical assistance. They were unable to write the numbers that they needed to (e.g. they wanted to write 4 but wrote 3). However, most of those students still understood the concept of subtraction as taking something away. I do need to work with them for short intense periods of time during IWT to ensure that they learn their numbers or they may end up being frustrated by future lessons.