1st Grade Task: Farmer Cason

Standards & Objectives

Learning objectives:

Students will:

Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.
Apply properties of operations as strategies to add and subtract.
Compare two two-digit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and <.
Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.

Essential and guiding questions:

Tell me why you chose to draw/use manipulatives/add the way you did to get your final answer.

What method did you use to add 10 to your answer in Part 1?

Why did you choose that mathematical symbol? Does it match your words?

Could you add in a different order and get the same answer?

If we added 30 instead of ten, what would your answer be?

If Farmer Cason bought 5 more horses, would this change your answer? Why or why not?

How many numbers are you adding? Can you represent this by drawing a model?

How does adding ten change a two-digit number? How do you know?

What two numbers are we comparing? Which symbol represents

what you are stating to be true?

Activity/Task Variations

Blooms taxonomy level:

Applying

Extension suggestions:

If Old MacDonald did sell 4 cows and got 8 chickens in return, which animal would he have more of (cows, chickens, or horses)? How do you know? Explain in your own words and use appropriate mathematical symbols to compare the three numbers.

Originator:

Tennessee Department of Education