CK-12.org's third grade math textbook

Ck-12.org's Third grade math textbook (8 year old) - a view by k-12math.info
Information | return to proposed CK-12 k-5 math screen

The following terms are developed and/or defined in this grade level's materials.
ADD BY REGROUPING (WHOLE NUMBER)	FREQUENCY TABLE	PROBLEM SOLVING
ADDITION (FRACTION)	HEXAGON	QUADRILATERAL
ANGLE	IDENTITY (ADDITION)	RAY
AREA	IDENTITY (MULT.)	RECTANGLE
ARRAY (MULT.) (WHOLE)	INEQUALITY SIGN	RECTANGLE (AREA)
ASSOCIATIVE (ADDITION)	LINE	RHOMBUS
BAR GRAPH	LINE SEGMENT	RIGHT ANGLE
COMMUTATIVE (ADDITION)	NUMERATOR	RIGHT TRIANGLE
DENOMINATOR	ORDER OF OPERATIONS	ROUNDING
DISTRIBUTIVE (WHOLE)	PARALLEL LINES	SQUARE
DIVISION (WHOLE)	PENTAGON	SYMBOLS FOR MULTIPLICATION.
DIVISOR, QUOTIENT	PERIMETER	TIME
EQUATION	PERPENDICULAR LINES	TRAPEZOID
EQUIVALENT FRACTIONS	PICTOGRAPH	VARIABLE
ESTIMATING SUMS	PLACE VALUE	VERTEX (ANGLE)
EVEN AND ODD NUMBER	POINT
FACTOR (WHOLE)	POLYGON





The following terms appear in this grade level's materials. At this grade level the terms are used in the lesson proper in examples or illustrations. The purpose here is to reinforce understanding of the terms.
ADD AND SUBTRACTION RELATION	MEASUREMENT (LENGTH	REPEATED SUBT.
ADDEND (WHOLE)	MULT. AND DIVISION RELATION	RULER
ADDITION (WHOLE)	MULT. PROPERTIES	SET
COLLECTING	MULTIPLES OF TEN	SHAPE
CURVE	MULTIPLICATION (WHOLE)	SUBTRACTION
DIVISION BY ZERO	NUMBER LINE	SYMBOLS FOR ADDITION
DIVISION WITH NUMBER LINE	NUMBER LINE (FRACTION)	SYMBOLS FOR DIVSION
FRACTION	NUMBER SENTENCE	TRIANGLE
INCH	ORDERING (NUMBERS)	TRUE AND FALSE
INTERPRETATION	ORDINAL NUMBER	UNKNOWN
INTERSECTING LINES	REMAINDER	WHOLE NUMBER
MEASUREMENT	REPEATED ADDITION	WRITING NUMBERS





A synonym of the following terms are used. The synonym helps to bridge the learner's non mathematical experiences to mathematics terms that will more formally be worked on. A synonym may also be used because these historical terms may have been replaced by a new vocabulary (k-12math.info's list of 1,000 terms has not changed in 40 years). Wiktionary dictonary may help here.
ADD. COMBINATIONS (WHOLE)	INEQUALITY (FRACTION)	SYMBOLS OF GROUPING
ALGEBRAIC EXPRESSIONS	MULT. COMBINATIONS	THREE ADDENDS
CONGRUENT PARTS (FRACTION)	MULTIPLES OF TWO	WORD PROBLEMS (WHOLE)
DIVISION COMBINATIONS	PERIMETER (QUADRILATERAL)
INEQUALITY (NUMBERS)	PIE APPROACH (FRACTION)

K-12math.info selected the content that appears here. All terms appear in the lesson proper. The selection process is based upon a content analysis of 2013 to advance copies of 2015 student mathematics textbook series. Series that base their content on 2010 and/or 2012 standards. The analysis also included content that was felt would be needed for the transistion to CK-12 existing textbook series.

Editor's Note: This is a very basic outline of the content and how they are to be developed in the lesson proper. These terms need to be used in examples, illustrations, class activities and homework to help further understand them.

Resources:
Learners age 5 to 11 Grades K through 6 (from Wikieducator's "Come fly with me..." project).
Key points in Writing a textbook. (Especially step 7)
Teaching OER Mathematics.
Learning design a Wikieducator.org project.

Additional observations made while collecting information for this site on unit development in a textbook:

One type has a chapter unit divided into 3 parts:
Part 1 has a written explanation of the concept being developed (or defined).
Part 2 has examples and illustrations of the concept.
Part 3 classroom and/or homework activities.

Another approach consists of 2 parts:
Part 1: the concept being developed (or defined) is being used in several carefully designed examples and illustrations.
Part 2: classroom and/or homework activities.