Curated OER
Making a Ten
An addition table supports third graders as they learn strategies to improve their math fluency. When finding sums greater than ten, young scholars are taught how to first make a ten and then add on the rest. A similar method is also...
Illustrative Mathematics
Equivalent fractions approach to non-repeating decimals
Trying to get your class to think of decimals as fractions and vice versa can lead to interesting discussions. After all, we can usually understand quickly that 1/4 is .25 but why is 1/7 not so easy to convert? This activity looks at...
Illustrative Mathematics
$20 Dot Map
Challenge the addition skills of young learners with this open-ended math problem. The task is simple, get from start to finish by connecting a series of three numbers. The trick is that the sum of the numbers must be less than or equal...
Balanced Assessment
Pick a Pattern or Two
Math is all about finding patterns. In this ask, scholars first investigate a sequence formed by squaring the sum of the digits in the previous term. They go on to investigate a second sequence and write an algebraic expression for this...
EngageNY
Solving Problems by Finding Equivalent Ratios
Combine total quantities and equivalent ratios in problem solving. The fifth lesson in a series of 29 presents problems that can be solved using equivalent ratios. Pupils use part-to-part ratios and either sums or differences of the...
Illustrative Mathematics
A Bobbie Bear's Buttons
Young mathematicians help Bobbie Bear pick colored buttons out of a box as they learn how to decompose numbers less than 10 into pairs of smaller numbers. To support students with the process, consider creating a worksheet or graphic...
Illustrative Mathematics
Make 9
Learning how numbers are put together as parts and wholes is a big step in building the foundational number sense of young mathematicians. Here, children are given a number less than 10 and are asked to find as many pairs of numbers as...
Illustrative Mathematics
Equivalent Expressions
Here is a straight-forward problem of multiplying two binomials with a twist. It is up to algebra learners to decide how to turn this product of sums into a sum of products. However, it is not the quadratic that is the answer; it is the...
EngageNY
The Mean as a Balance Point
It's a balancing act! Pupils balance pennies on a ruler to create a physical representation of a dot plot. The scholars then find the distances of the data points from the balance point, the mean.
EngageNY
Divisibility Tests for 3 and 9
Who knew the sum of a number's digits gives such interesting information? The 18th installment of a 21-part module has scholars investigate division by three and nine. After looking at several examples, they develop divisibility tests...
Illustrative Mathematics
Mixed Numbers with Unlike Denominators
There is more than one way to add mixed numbers. This learning exercise asks 5th graders to find and record two ways. The purpose is to help pupils realize there are different ways to reach a common solution in math. The two most common...
Curated OER
Dice Addition
Using the provided tracing number worksheet, a pair of kindergartners will practice their adding skills. Player A will roll two die, add the sum, and then trace the sum on the worksheet. Player B will take a turn and do the same. The...
Curated OER
Tetrahedral Dice
Put those thinking hats on and look at all the possible outcomes from rolling two different four-sided dice. The challenge in this problem is finding all the combinations when adding and subtracting the numbers from each die and creating...
Inside Mathematics
Circles in Triangles
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
EngageNY
Addition and Subtraction Formulas 1
Show budding mathematicans how to find the sine of pi over 12. The third lesson in a series of 16 introduces the addition and subtraction formulas for trigonometric functions. Class members derive the formulas using the distance formula...
Virginia Department of Education
How Many Triangles?
Something for young mathematicians to remember: the sum of any two sides must be greater than the third. Class members investigates the Triangle Inequality Theorem to find the relationship between the sides of a triangle. At the same...
EngageNY
Estimating Probabilities by Collecting Data
Take a spin to determine experimental probability. Small groups spin a spinner and keep track of the sums of the spins and calculate the resulting probabilities. Pupils use simulated frequencies to practice finding other probabilities to...
Curated OER
T Points from Directions
Here is a lesson that starts with having geometers translate points using compass directions into an accurate picture of the problem. Then they must use their knowledge of the Pythagorean theorem or similar triangles to solve. This makes...
Illustrative Mathematics
Rectangle Perimeter 2
While this activity is centered around expressions that represent the perimeter of a rectangle, it also hits at the fundamental concept of equivalent expressions, simplifing expressions, and like-terms. Classmates express their...