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141_Focusing on the Development of Children’s Mathematical Thinking: CGI

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Focusing on the Development of
Children’s Mathematical
Thinking: CGI
Megan Loef Franke
UCLA


Algebra as focal point


“Algebra for All”
(Edwards, 1990; Silver, 1997)



“gatekeeper for
citizenship”
(Moses & Cobb, 2001)



Difficult transition from
arithmetic



Not move high school
curriculum to elementary
school




Engages teachers in a new
way, new content


Algebra as generalized arithmetic
and the study of relations


Viewing the equal sign as a
relation
57 + 36 =  + 34



Using number relations to
simplify calculations
5 x 499 = 



Making explicit general
relations based on fundamental
properties of arithmetic
768 + 39 = 39 + 


Equality

8+4= +5



Equality Data (8+4= 
+5)
Student Responses1

1

Grade

7

12

17

12 & 17

1st & 2nd

5%

58

13

8

3rd & 4th


9

49

25

10

5th & 6th

2

76

21

2

Falkner, K., Levi, L., & Carpenter, T. (1999). Children’s understanding of
equality: A foundation for algebra. Teaching Children Mathematics, 6, 232-6.



True/false number sentences:
from worksheets to index cards







Shift from a focus
on answer to a
focus on reasoning
Shift from a focus
on a single problem
to a sequence
Shift from sharing a
single strategy to a
conversation
around the
reasoning


Sequence of Number
Sentences
3+4=7
5 + 5 = 8*
7=3+4
6=6+0
6=6
6=3+3
4+2=3+3
* denotes false number sentence


Mathematical Content
Equality
Number Facts
Place Value

Number Sense
Mathematical Properties
Multiplication
Equivalence

7=7
5+5=4+6
250 + 150 =  +100
45 = 100 + 20 + 
5+6=6+
3× 7=7+7+7
½=¼+¼


Relational Thinking

24 + 17 – 17 = 34 + 

1,000 – 395 = ___
999 – 395 + 1


Relational Thinking


Solve:



576 + 199 = □





1,000 – 637 = □




576 + 200 - 1

999 – 637 + 1

4 x 24 + 5 x 24 = □


10 x 24 - 24


Generating Conjectures
Making relational thinking explicit

Representing
Conjectures
 
b+0 = b
 
c+d = d+c



Variables
k + k + 13 = k + 20


Experimental Study Design


Volunteer, urban, low
performing elementary schools
in one district (19)



District working to improve
opportunities in mathematics



Schools randomly assigned to
year 1 or year 2 professional
development work



School site based PD monthly



On site support




End of one year assessed
teachers (180) and students
(3735)


Teacher Findings
Generating strategies for 8 + 4 =  + 5






No differences in
teachers’ perceptions on
time spent on algebraic
thinking tasks in
classrooms
No differences on
knowledge of algebra
Differences in teachers’
knowledge of student
thinking- strategies and
relational thinking

Numb
er of
strate

gies

Participat Noning
Participati
Teachers ng
Teachers

1

6%

44%

2

38%

41%

3

25%

12%

4 or
more

31%


4%


Student Findings


Students in algebraic
thinking classrooms
scored significantly
better on the
equality written
assessment.



Students in 3rd and
5th grades were twice
as likely to use
relational thinking



Publications


Book for teachers:

Carpenter, T., Franke, M., & Levi, L. (2003).
Thinking mathematically Integrating
arithmetic and algebra in elementary school.

Portsmouth, NH: Heinemann.


Research article:

Jacobs, V., Franke, M., Carpenter, T., Levi, L. &
Battey, D. (in press). Exploring the impact of
large scale professional development focused
on children’s algebraic reasoning. Journal for
Research in Mathematics Education.


Conjectures


Is a focus on children’s thinking
enough?


Show what students are capable of



Counter narratives



Change what we consider basic skills




Create ways in schools to make room for
understanding



Watch for how the status quo limits
opportunities…find ways to challenge it



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