Math Games

2.N.1

Say the number sequence from 0 to 100 by • 2s, 5s, and 10s, forward and backward, using starting points that are multiples of 2, 5, and 10 respectively • 10s using starting points from 1 to 9 • 2s starting from 1 • Extend a skip-counting sequence by 2s, 5s, or 10s forward and backward. • Skip-count by 10s, given any number from 1 to 9 as a starting point. • Count by 2s starting from 1 or from any odd number. • Identify and correct errors and omissions in a skip-counting sequence. • Count a sum of money with pennies, nickels, or dimes (to 100¢). • Count quantity using groups of 2s, 5s, or 10s and counting on.

2.N.10

Apply mental mathematics strategies, including • using doubles • making 10 • using one more, one less • using two more, two less • building on a known double • using addition for subtraction to develop recall of basic addition facts to 18 and related subtraction facts. • Explain the mental mathematics strategy that could be used to determine an addition or subtraction fact, such as - using doubles (e.g., for 4 + 6, think 5 + 5) - using doubles plus one (e.g., for 4 + 5, think 4 + 4 + 1) - using doubles take away one (e.g., for 4 + 5, think 5 + 5 – 1) - using doubles plus two (e.g., for 4 + 6, think 4 + 4 + 2) - using doubles take away two (e.g., for 4 + 6, think 6 + 6 – 2) - making 10 (e.g., for 7 + 5, think 7 + 3 + 2) - building on a known double (e.g., 6 + 6 = 12, so 6 + 7 = 12 + 1 = 13) - using addition for subtraction (e.g., for 7 – 3, think 3 + ? = 7) • Use and describe a personal strategy for determining a sum to 18 and the corresponding subtraction.

2.N.2

Demonstrate if a number (up to 100) is even or odd. • Determine if a number is even or odd by using concrete materials or pictorial representations. • Identify even and odd numbers in a sequence, such as in a hundred chart. • Sort a set of numbers into even and odd.

2.N.3

Describe order or relative position using ordinal numbers. • Indicate the position of an object in a sequence by using ordinal numbers. • Compare the relative position of an object in two different sequences.

2.N.4

Represent and describe numbers to 100, concretely, pictorially, and symbolically. • Represent a number using concrete materials, such as ten frames and base-10 materials. • Represent a number using coins (pennies, nickels, dimes, and quarters). • Represent a number using tallies. • Represent a number pictorially. • Represent a number using expressions (e.g., 24 + 6, 15 + 15, 40 – 10). • Read a number (0–100) in symbolic or word form. • Record a number (0–20) in words. • Determine compatible number pairs for 20 or 50.

2.N.5

Compare and order numbers up to 100. • Order a set of numbers in ascending or descending order, and verify the result using a hundred chart, number line, ten frames, or by making reference to place value. • Identify errors in an ordered sequence. • Identify missing numbers in a hundred chart. • Identify errors in a hundred chart.

2.N.6

Estimate quantities to 100 using referents. • Estimate a quantity by comparing it to a referent (known quantity). • Estimate the number of groups of 10 in a quantity using 10 as a referent. • Select between two possible estimates for a quantity, and explain the choice.

2.N.7

Illustrate, concretely and pictorially, the meaning of place value for numbers to 100. • Explain and show with counters the meaning of each digit for a 2-digit numeral with both digits the same (e.g., for the numeral 22, the first digit represents two tens [twenty counters] and the second digit represents two ones [two counters]). • Count the number of objects in a set using groups of 10s and 1s, and record the result as a 2-digit numeral under the headings of 10s and 1s. • Describe a 2-digit numeral in at least two ways (e.g., 24 as two tens and four ones, twenty and four, two groups of ten and four left over, and twenty-four ones). • Illustrate using 10 frames and diagrams that a numeral consists of a certain number of groups of 10 and a certain number of 1s. • Illustrate using proportional base-10 materials that a numeral consists of a certain number of tens and a certain number of ones. • Explain why the value of a digit depends on its placement within a numeral.

2.N.8

Demonstrate and explain the effect of adding zero to or subtracting zero from any number. • Add zero to a number and explain why the sum is the same as the addend. • Subtract zero from a number and explain why the difference is the same as the number

2.N.9

Demonstrate an understanding of addition (limited to 1- and 2-digit numerals) with answers to 100 and the corresponding subtraction by • using personal strategies for adding and subtracting with and without the support of manipulatives • creating and solving problems that involve addition and subtraction • explaining that the order in which numbers are added does not affect the sum • explaining that the order in which numbers are subtracted may affect the difference • Model addition and subtraction using concrete materials or visual representations, and record the process symbolically. • Create an addition or a subtraction number sentence and a story problem for a solution. • Solve a problem involving a missing addend, and describe the strategy used. • Solve a problem involving a missing minuend or subtrahend, and describe the strategy used. • Match a number sentence to a missing addend problem. • Match a number sentence to a missing subtrahend or minuend problem. • Add a set of numbers in two different ways, and explain that the sum is the same (e.g., 2 + 5 + 3 + 8 = 2 + 3 + 5 + 8 or 5 + 3 + 8 + 2).

2.SS.1

Relate the number of days to a week and the number of months to a year in a problem-solving context. • Read a date on a calendar. • Name and order the days of the week. • Identify the day of the week and the month of the year for an identified calendar date. • State that there are seven days in a week and twelve months in a year. • Determine whether a set of days is more or less than a week. • Identify yesterday’s/tomorrow’s date. • Identify the month that comes before and the month that comes after a given month. • Name and order the months of the year. • Solve a problem involving time that is limited to the number of days in a week and the number of months in a year.

2.SS.2

Relate the size of a unit of measure to the number of units (limited to non-standard units) used to measure length and mass (weight). • Explain why one of two non-standard units may be a better choice for measuring the length of an object. • Explain why one of two non-standard units may be a better choice for measuring the mass of an object. • Select a non-standard unit for measuring the length or mass of an object, and explain why it was chosen. • Estimate the number of non-standard units needed for a measurement task. • Explain why the number of units of a measurement will vary depending upon the unit of measure used.

2.SS.3

Compare and order objects by length, height, distance around, and mass (weight) using non-standard units, and make statements of comparison. • Estimate, measure, and record the length, height, distance around, or mass (weight) of an object using non-standard units. • Compare and order the measure of two or more objects in ascending or descending order, and explain the method of ordering.

2.SS.4

Measure length to the nearest non-standard unit by • using multiple copies of a unit • using a single copy of a unit (iteration process) • Explain why overlapping or leaving gaps does not result in accurate measures. • Count the number of non-standard units required to measure the length of an object using a single copy or multiple copies of the same unit of measure. • Estimate and measure an object using multiple copies of a non-standard unit and using a single copy of the same unit many times, and explain the results. • Estimate and measure, using non-standard units, a length that is not a straight line. • Create different rulers, using non-standard units of measure, and use these rulers to measure length.

2.SS.5

Demonstrate that changing the orientation of an object does not alter the measurements of its attributes. • Measure an object, change the orientation, re-measure, and explain the results

2.SS.6

Sort 2-D shapes and 3-D objects using two attributes, and explain the sorting rule. • Determine the differences between two pre-sorted sets, and explain the sorting rule. • Identify and name two common attributes of items within a sorted group. • Sort a set of 2-D shapes (regular and irregular) according to two attributes, and explain the sorting rule. • Sort a set of 3-D objects according to two attributes, and explain the sorting rule.

2.SS.7

Describe, compare, and construct 3-D objects, including • cubes • spheres • cones • cylinders • prisms • pyramids • Sort a set of 3-D objects, and explain the sorting rule. • Identify common attributes of cubes, spheres, cones, cylinders, prisms, or pyramids from sets of the same 3-D objects. • Identify and describe 3-D objects with different dimensions. • Identify and describe 3-D objects with different orientations. • Create and describe a representation of a 3-D object using materials such as modelling clay. • Identify examples of cubes, spheres, cones, cylinders, prisms, or pyramids found in the environment.

2.SS.8

Describe, compare, and construct 2-D shapes, including • triangles • squares • rectangles • circles • Sort a set of 2-D shapes, and explain the sorting rule. • Identify common attributes of triangles, squares, rectangles, or circles from sets of the same type of 2-D shapes. • Identify 2-D shapes with different dimensions. • Identify 2-D shapes with different orientations. • Create a model to represent a 2-D shape. • Create a pictorial representation of a 2-D shape.

2.SS.9

Identify 2-D shapes as parts of 3-D objects in the environment. • Compare and match a 2-D shape, such as a triangle, square, rectangle, or circle, to the faces of 3-D objects in the environment. • Name the 2-D faces of a 3-D object.

2.PR.1

Predict an element in a repeating pattern using a variety of strategies. • Identify the core of a repeating pattern. • Describe and extend a pattern with two attributes. • Explain the rule used to create a repeating non-numerical pattern. • Predict an element in a repeating pattern using a variety of strategies. • Predict an element of a repeating pattern, and extend the pattern to verify the prediction.

2.PR.2

Demonstrate an understanding of increasing patterns by • describing • reproducing • extending • creating patterns using manipulatives, diagrams, sounds, and actions (numbers to 100). • Identify and describe increasing patterns in a variety of contexts (e.g., hundred chart, number line, addition tables, calendar, a tiling pattern, or drawings). • Represent an increasing pattern concretely and pictorially. • Identify errors in an increasing pattern. • Explain the rule used to create an increasing pattern. • Create an increasing pattern and explain the pattern rule. • Represent an increasing pattern using another mode (e.g., colour to shape). • Solve a problem using increasing patterns. • Identify and describe increasing patterns in the environment (e.g., house/room numbers, flower petals, book pages, calendar, pine cones, leap years). • Determine missing elements in a concrete, pictorial, or symbolic increasing pattern, and explain the reasoning.

2.PR.3

Demonstrate and explain the meaning of equality and inequality by using manipulatives and diagrams (0 to 100). • Determine whether two quantities of the same object (same shape and mass) are equal by using a balance scale. • Construct and draw two unequal sets using the same object (same shape and mass), and explain the reasoning. • Demonstrate how to change two sets, equal in number, to create inequality. • Choose from three or more sets the one that does not have a quantity equal to the others, and explain why.

2.PR.4

Record equalities and inequalities symbolically using the equal symbol or the not-equal symbol. • Determine whether two sides of a number sentence are equal (=) or not equal (≠). Write the appropriate symbol and justify the answer. • Model equalities using a variety of concrete representations, and record. • Model inequalities using a variety of concrete representations, and record symbolically.

2.SP.1

Gather and record data about self and others to answer questions. • Formulate a question that can be answered by gathering information about self and others. • Organize data as it is collected using concrete objects, tallies, checkmarks, charts, or lists. • Answer questions using collected data.

2.SP.2

Construct and interpret concrete graphs and pictographs to solve problems. • Determine the common attributes of concrete graphs by comparing a set of concrete graphs. • Determine the common attributes of pictographs by comparing a set of pictographs. • Answer questions pertaining to a concrete graph or pictograph. • Create a concrete graph to display a set of data and draw conclusions. • Create a pictograph to represent a set of data using one-to-one correspondence. • Solve a problem by constructing and interpreting a concrete graph or pictograph.