Addition and Subtraction Concepts 63
Successful Strategies
One of the foundational concepts associated with adding
and subtracting tens is rational counting by tens. Encourage
students to skip count by tens beginning with zero and
with numbers other than zero. To further help students
understand the adding and subtracting tens concept, use base
ten manipulatives or drawings to model the computation.
tens, add, addition,
subtract, subtraction,
minus sign, plus sign
Math Words to Use
Questions at Different Levels of Cognitive Demand
Recall: What is 53 + 10?
Comprehension: How do you add ten to a number?
Application: How would you use 92 – 10 to solve
92 – 20?
Analysis: Which facts go together? Why?
Evaluation: How does skip counting help us add and
subtract ten?
Synthesis: How could you use the adding and
subtracting tens concept to add and subtract nines?
EASY
COMPLEX