Pre-K-2
Students are introduced to the concepts of greater than, less than and equal to
by observing quantities and making comparisons. Using various
instructional materials such as modeling clay, buttons, beans, and
cotton balls, students create amounts to compare using the open-mouthed
fish. Depending which fish is chosen, the fish cut-out (with its mouth
open) represents either greater than or less than. For equivalent amounts, a clam cut-out represents equal to.
This introductory lesson can be assessed through visual observation
and verbal questioning. A group size of 3 – 6 students per group is
optimal.
Pre-K-2
In this lesson, the relationship of subtraction to addition is
introduced with a book and with dominoes. Then students explore the
concept of missing addends.
Pre-K-2
In this lesson, the students focus on dominoes with the same number of spots
on each side and on the related addition facts. They make triangle-shaped flash
cards for the doubles facts.
Pre-K-2
This lesson encourages students to explore another model of addition,
the balance model. The exploration also involves recording the modeled
addition facts in equation form. Students begin to memorize the
addition facts by playing the “seven-up game.”
Pre-K-2
This lesson builds on the previous two lessons and encourages students
to explore another model for addition, the set model. This model is
similar to the counting model in the first lesson, because it is based
on counting. Reading a related counting and addition book sets the
stage for this lesson in which students write story problems, find sums
using sets, and present results in the form of a table. In the
discussion of the table, the students focus on the order property and
the effects of adding 0.
Pre-K-2, 3-5
In this lesson, students generate sums using the number line model.
This model highlights the measurement aspect of addition and is a
distinctly different representation of the operation from the model
presented in the previous lesson. The order (commutative) property is
also introduced. At the end of the lesson, students are encouraged to
predict sums and to answer puzzles involving addition.
Pre-K-2
This lesson focuses on the counting model for addition and begins with
reading a counting book. Students model the numbers with counters as
the book is read. Then they count the spots on each side of a domino
and write, in vertical and horizontal format, the sums suggested by
dominoes. Finally, the students illustrate a domino and record a sum it
represents.
