1 / 22

# Operations and Algebraic Thinking

Operations and Algebraic Thinking. November 15, 2012. Algebra…. Where have you seen students use or apply algebraic reasoning? Where have you seen students struggle with algebraic ideas? . Refreshing our memory…. Glossary, Table 1 – take it out if you have it .

Télécharger la présentation

## Operations and Algebraic Thinking

E N D

### Presentation Transcript

1. Operations and Algebraic Thinking November 15, 2012

2. Algebra… • Where have you seen students use or apply algebraic reasoning? • Where have you seen students struggle with algebraic ideas?

3. Refreshing our memory… • Glossary, Table 1 – take it out if you have it

4. Problem Types: Agree or Disagree • The problem types are research-based and come from research with young children doing these tasks.

5. Problem Types: Agree or Disagree • This idea of problem types are all over Investigations curriculum in various grades.

6. Problem Types: Agree or Disagree • When we think about problem types with addition and subtraction it does not matter at all about how students “solve” tasks (e.g., manipulatives, drawing, counting, number lines).

7. Problem Types: Agree or Disagree • Writing tasks to fit a specific problem type is a tasks that most of my teachers can do.

8. Problem Types and their history • Cognitively Guided Instruction • Problem Types (Types of tasks) • Is that all there is to CGI ?????? • Does it matter how students solve these problems? Why or why not?

9. Problem Types and their history • Cognitively Guided Instruction • Problem Types (Types of tasks) • Methods in which students solve tasks • Decisions that teachers go through to formatively assess students AND then pose follow-up tasks

10. Methods • Direct Modeling • Counting Strategies • Algorithms or Derived Facts • There were 8 seals playing. 3 seals swam away. How many seals were still playing? • What would each of these 3 look like in a Grade 1 classroom?

11. Methods • Direct Modeling • Separate (Result Unknown) • There were 8 seals playing. 3 seals swam away. How many seals were still playing? • A student would….. • A set of 8 objects is constructed. 3 objects are removed. The answer is the number of remaining objects.

12. Methods • Counting Strategies • Separate (Result Unknown) • There were 8 seals playing. 3 seals swam away. How many seals were still playing? • A student would….. • Start at 8 and count backwards 3 numbers. The number they end on would be their answer.

13. Methods • Invented algorithms /derived strategies • Separate (Result Unknown) • There were 8 seals playing. 3 seals swam away. How many seals were still playing? • What would students do? • “4 plus 4 is 8, so 8 minus 4 is 4. But I am only taking away 3 so there should be 5 seals playing.”

14. Direct modeling, counted or invented strategy? • There were 8 seals playing. 3 seals swam away. How many seals were still playing? • The student starts at 8 on a number line and count backwards 3 numbers. The number they land on is their answer. • The student puts 3 counters out and adds counters until they get to 8. The number of counters added is their answer.

15. Direct modeling, counted or invented strategy? • There were 8 seals playing. 3 seals swam away. How many seals were still playing? • The student draws 8 tallies and crosses out 3. The number left is their answer. • The student starts at 3 and counts up until they get to 8. As the student counts they put a finger up (1 finger up as they say 4, 5, 6, 7, 8). The number of fingers up is their answer.

16. How students solve problems • Does it matter what students strategy is? Why? • What does it look like for students to be proficient with a problem type?

17. Common Core Connection • “Fluently add and subtract” • What do we mean when students are fluent? • Fluently (Susan Jo Russell, Investigations author) • Accurate, Efficient, Flexible • What do these mean? • Where do basic facts tests fit in?

18. Task Modification • Investigations Unit– examine a number sense unit • Look for “opportunities” to modify tasks to match “more difficult” task types • Modify/write tasks • What is an appropriate size of numbers? • What are the task types? • How would you assess?

19. Teaching experiment… • Select students who are struggling • Pose a few problems for a problem type • Observe and question • Pose a follow-up task that “meets them where they are”

20. Working with Large Numbers • On your own solve 4,354 – 3,456 + 455 in three different ways • Write a story problem to match this problem. • Pick one of your strategies… how did algebraic reasoning help you complete the task?

21. 4,354 – 3,456 + 455 • Gallery Walk • Explore various strategies and explanations • Any commonalities or frequently occurring ideas?

22. 4,354 – 3,456 + 455 • Sharing out strategies • How can estimation help us BEFORE we start? • Rounding…. Rounding to which place helps us get the best estimate? • What is the point of rounding?

More Related