Experiment with transformations in the plane High School | Students learn how shapes move, flip, and rotate on a flat surface without changing size or form. This is the foundation for understanding when two shapes are identical. | G.CO.A |
Know precise definitions of angle, circle, perpendicular line, parallel line High School | Students memorize exact definitions for basic shapes and lines: what makes two lines parallel, what defines a circle, and what separates a line segment from a full line. These definitions become the foundation for every proof and figure that follows. | G.CO.A.1 |
Represent transformations in the plane and describe transformations as… High School | Students learn how slides, flips, and rotations move points on a graph, then sort those moves into two groups: ones that keep shapes the same size and angle, and ones that stretch or distort them. | G.CO.A.2 |
Describe the rotations and reflections that carry a given figure High School | Students identify which flips and turns map a shape exactly back onto itself. A square, for example, can be rotated a quarter turn or reflected across its center line and still look unchanged. | G.CO.A.3 |
Develop definitions of rotations, reflections High School | Students practice the precise rules behind slides, flips, and turns by connecting each move to geometry concepts like parallel lines and circles. The goal is defining these movements exactly, not just describing them loosely. | G.CO.A.4 |
Draw the transformation High School | Students draw what a shape looks like after it has been slid, flipped, or turned. Given a starting figure, they produce the new position on the page. | G.CO.A.5 |
Specify a sequence of transformations that will carry a given figure onto… High School | Students describe the exact steps (slides, flips, or turns) needed to move one shape onto another so they line up perfectly. | G.CO.A.6 |
Understand congruence in terms of rigid motions High School | Rigid motions are moves that slide, flip, or rotate a shape without changing its size. Students use these moves to show that two shapes are congruent, meaning they match exactly. | G.CO.B |
Use geometric descriptions of rigid motions to transform figures and to predict… High School | Rigid motions are slides, flips, and turns that move a shape without changing its size or angles. Students use these moves to show whether two shapes are congruent, meaning one maps exactly onto the other. | G.CO.B.7 |
Use the definition of congruence in terms of rigid motions to show that two… High School | Two triangles are congruent when their matching sides and angles are equal. Students show this by proving the triangles can be flipped, slid, or rotated to land exactly on top of each other. | G.CO.B.8 |
Explain how the criteria for triangle congruence High School | Students show why two triangles with matching angles and sides must be identical in size and shape, using the idea that one triangle can be flipped, slid, or rotated onto the other without any stretching. | G.CO.B.9 |
Prove geometric theorems and, when appropriate, the converse of theorems High School | Students prove that geometric rules always hold, such as why opposite angles formed by two crossing lines are always equal or why the angles in any triangle always add up to 180 degrees. The work requires a logical chain of steps, not just a correct answer. | G.CO.C |
Prove theorems about lines and angles High School | Students write formal proofs about how angles behave when lines cross, including why parallel lines create matching angles and why a perpendicular bisector marks the exact midpoint between two points. | G.CO.C.10 |
Prove theorems about triangles High School | Students prove the rules that make triangles predictable: why the three interior angles always add to 180 degrees, why equal sides force equal angles, and why the line connecting two midpoints runs parallel to the base at exactly half its length. | G.CO.C.11 |
Prove theorems about parallelograms High School | Students prove that parallelograms follow predictable rules: opposite sides match in length, opposite angles match in measure, and the two diagonals cut each other exactly in half. | G.CO.C.12 |
Prove theorems about polygons High School | Students prove why interior and exterior angles in polygons follow predictable rules, then use those rules to solve real problems. Think of it as moving from "this is always true" to "here's why." | G.CO.C.12.a |
Make geometric constructions High School | Students use a compass and straightedge to draw precise geometric shapes, such as a copied angle or a bisected line segment, without measuring tools. | G.CO.D |
Make formal geometric constructions with a variety of tools and methods High School | Students use a compass, straightedge, or folded paper to draw precise geometric figures: copying a segment or angle, splitting one in half, and drawing perpendicular or parallel lines. | G.CO.D.13 |
Construct an equilateral triangle, a square High School | Using only a compass and straightedge, students draw a perfect triangle, square, and six-sided shape that fit exactly inside a circle, with every corner touching the edge. | G.CO.D.14 |
Understand similarity in terms of similarity transformations High School | Similarity transformations are moves like scaling, rotating, or flipping a shape so it stays the same shape but changes size. Students learn to recognize and explain when two figures are similar using those transformations. | G.SRT.A |
Verify experimentally the properties of dilations given by a center and a scale… High School | A dilation stretches or shrinks a shape by a fixed amount from a center point. Students test what stays the same (angles, parallel lines) and what changes (side lengths) when a figure is scaled up or down. | G.SRT.A.1 |
A dilation takes a line not passing through the center of the dilation to a… High School | Dilations scale figures up or down from a fixed center point. A line through that center stays in place; any other line shifts but stays parallel to where it started. | G.SRT.A.1.a |
The dilation of a line segment is longer or shorter in the ratio given by the… High School | When a line segment is scaled up or down, its new length equals the original length multiplied by the scale factor. A segment scaled by 3 becomes three times as long; scaled by one-half, it becomes half as long. | G.SRT.A.1.b |
Use the definition of similarity to decide if two given figures are similar High School | Two shapes are similar if one can be scaled, rotated, or reflected to match the other exactly. Students identify whether two triangles are similar by checking that all matching angles are equal and all matching sides are in the same ratio. | G.SRT.A.2 |
Use the properties of similarity transformations to establish the Angle-Angle High School | Two triangles are similar if two of their angles match, meaning the triangles have the same shape even if different sizes. Students prove why that two-angle match is enough, using what they know about how shapes scale. | G.SRT.A.3 |
Prove theorems involving similarity High School | Students prove that two shapes are similar by showing their angles match and their sides scale by the same ratio. This includes writing formal proofs about triangles using angle relationships and proportional sides. | G.SRT.B |
Prove theorems about triangles High School | Students prove why triangles work the way they do, including why a line drawn parallel to one side splits the other two sides in equal proportions and why the Pythagorean Theorem holds up using the logic of similar triangles. | G.SRT.B.4 |
Use congruence and similarity criteria for triangles to solve problems and to… High School | Students use the rules of congruent and similar triangles to solve geometry problems and explain why certain shapes or measurements must be equal. This includes finding unknown side lengths, angles, and distances in real figures. | G.SRT.B.5 |
Define trigonometric ratios and solve problems involving right triangles High School | Trigonometric ratios connect the angles of a right triangle to the lengths of its sides. Students use those ratios to find a missing side or angle when they know two other measurements. | G.SRT.C |
Demonstrate understanding that by similarity, side ratios in right triangles… High School | In any right triangle, the ratio of two sides depends only on the angles, not the size of the triangle. That idea is the foundation of sine, cosine, and tangent. | G.SRT.C.6 |
Explain and use the relationship between the sine and cosine of complementary… High School | Sine and cosine are linked: the sine of any angle equals the cosine of its complement, and students use that connection to solve problems with triangles without needing a calculator for every step. | G.SRT.C.7 |
Use trigonometric ratios and the Pythagorean Theorem to solve right triangles… High School | Given a real-world situation involving a right triangle, students use sine, cosine, tangent, or the Pythagorean Theorem to find missing side lengths and angles. Think ramps, shadows, and roof slopes. | G.SRT.C.8 |
Apply trigonometry to general triangles High School | Trigonometry isn't just for right triangles. Students use sine and cosine rules to find missing angles and side lengths in any triangle, including the kind that shows up in real maps, construction plans, and navigation problems. | G.SRT.D |
(+) Derive the formula A = ½ absin High School | Students find the area of any triangle using two side lengths and the angle between them, not just triangles with a known height. They work out where the formula comes from by dropping a perpendicular line from one corner to the opposite side. | G.SRT.D.9 |
(+) Prove the Laws of Sines and Cosines and use them to solve problems High School | Students use two rules that connect a triangle's angles to its side lengths to find missing measurements in any triangle, not just right triangles. | G.SRT.D.10 |
(+) Understand and apply the Law of Sines and the Law of Cosines to find… High School | When a triangle has no right angle, the usual shortcuts stop working. Students use the Law of Sines and the Law of Cosines to find missing side lengths and angles anyway. | G.SRT.D.11 |
Understand and apply theorems about circles High School | Circle theorems connect angles, arcs, and line segments inside or around a circle. Students use these relationships to solve problems about inscribed angles, tangent lines, and the parts of a circle that cross or meet at its edge. | G.C.A |
Prove that all circles are similar High School | Students show why any two circles are always the same shape, just different sizes, by explaining that one can always be scaled up or down to match the other exactly. | G.C.A.1 |
Identify and describe relationships among inscribed angles, radii High School | Students study the hidden rules that govern circles: why an angle formed inside a circle is always half the arc it cuts, why a radius always meets a tangent line at a perfect right angle, and how chords and arcs relate to each other. | G.C.A.2 |
Prove properties of angles for a quadrilateral and other polygons inscribed in… High School | Students prove that opposite angles in a four-sided shape drawn inside a circle always add up to 180 degrees. The work includes drawing the largest circle that fits inside a triangle and the smallest circle that fits around it. | G.C.A.3 |
(+) Construct a tangent line to a circle from a point outside the given circle High School | Given a point outside a circle, students draw the one straight line that just grazes the circle's edge at exactly one spot. This is an advanced geometry construction done with a compass and straightedge. | G.C.A.4 |
Find arc lengths and areas of sectors of circles High School | Students calculate how long a curved piece of a circle's edge is and how much area a pie-slice section covers. Both answers depend on the central angle and the radius. | G.C.B |
Derive using similarity the fact that the length of the arc intercepted by an… High School | Students learn why a wedge of a circle gets bigger as the radius grows, then use that relationship to define radian measure and calculate the area of a pie-slice region. | G.C.B.5 |
Translate between the geometric description and the equation for a conic… High School | Students convert between a written description of a circle, parabola, or ellipse and its algebraic equation. They work in both directions: starting from a graph or description to write the equation, and starting from an equation to describe the shape. | G.GPE.A |
Derive the equation of a circle of given center and radius using the… High School | Students learn where the equation for a circle comes from by connecting it to the Pythagorean Theorem. They also work backwards from an equation to find the circle's center point and its radius. | G.GPE.A.1 |
Derive the equation of a parabola given a focus and directrix High School | Students learn where a parabola comes from by working backward from two key pieces: a fixed point (the focus) and a fixed line (the directrix). From those two anchors, they build the equation that describes the curve. | G.GPE.A.2 |
(+) Derive the equations of ellipses and hyperbolas given the foci, using the… High School | Given two fixed points called foci, students figure out the equation of an ellipse or hyperbola by working with a distance rule: for an ellipse the distances from any point to each focus always add to the same total, and for a hyperbola they always subtract to the same amount. | G.GPE.A.3 |
(+) Use equations and graphs of conic sections to model real-world problems High School | Students use the equations and graphs of circles, ellipses, parabolas, and hyperbolas to solve real-world problems, such as modeling a satellite dish or a planet's orbit around the sun. | G.GPE.A.3.a |
Use coordinates to prove simple geometric theorems algebraically High School | Students use x-y coordinates and algebra to prove facts about shapes, like whether two lines are parallel or a point lands exactly at the midpoint of a segment. | G.GPE.B |
Use coordinates to prove simple geometric theorems algebraically, including the… High School | Students use x-y coordinates and the distance formula to prove that a shape has the properties it claims, such as showing that a figure is a true rectangle or that two lines are parallel. | G.GPE.B.4 |
Prove the slope criteria for parallel and perpendicular lines and use them to… High School | Parallel lines have the same slope; perpendicular lines have slopes that multiply to -1. Students use those two rules to prove relationships between lines and solve problems involving right angles and parallel paths on a coordinate grid. | G.GPE.B.5 |
Find the point on a directed line segment between two given points that… High School | Given two points on a graph, students find the exact spot between them that splits the distance into a specific ratio, like 1 to 3. This shows up in design, mapping, and any problem where an even split won't do. | G.GPE.B.6 |
Use coordinates to compute perimeters of polygons and areas of triangles and… High School | Students use coordinate points on a graph to calculate the perimeter of a shape or the area of a triangle or rectangle. They apply the distance formula to measure the length of each side without a physical ruler. | G.GPE.B.7 |
Explain volume formulas and use them to solve problems High School | Students learn where volume formulas come from and use them to find how much space a shape holds. This covers prisms, pyramids, cones, and spheres. | G.GMD.A |
Give an informal argument for the formulas for the circumference of a circle High School | Students explain *why* area and volume formulas work, not just how to use them. They reason through why the area of a circle or the volume of a cone comes out the way it does, using diagrams, comparisons, and informal logic. | G.GMD.A.1 |
(+) Give an informal argument using Cavalieri's principle for the formulas for… High School | Students explain why the volume formulas for spheres and cones actually work by comparing cross-sections of stacked layers. The logic relies on the idea that two solids with identical layer areas at every height have equal volumes. | G.GMD.A.2 |
Use volume formulas for cylinders, pyramids, cones High School | Students use formulas to find the volume of shapes like cans, funnels, ice cream cones, and balls. The problems involve real measurements, not just plugging in numbers. | G.GMD.A.3 |
Visualize relationships between two-dimensional and three-dimensional objects High School | Students picture how flat shapes become solid objects, like how a rectangle rotates to form a cylinder or how slicing a cone produces a circle. This connects what they draw on paper to the 3-D shapes around them. | G.GMD.B |
Identify the shapes of two-dimensional cross-sections of three-dimensional… High School | Slice a cone or a cylinder and name the flat shape you'd see cut through the middle. Students also picture what solid a spinning flat shape would carve out, like a rectangle spinning into a cylinder. | G.GMD.B.4 |
Apply geometric concepts in modeling situations High School | Students use shapes, measurements, and geometric reasoning to model real-world situations, like figuring out how much material a building needs or how far apart two objects are. | G.MG.A |
Use geometric shapes, their measures High School | Students look at a real object, like a building or a bridge, and figure out which geometric shape it most closely resembles. Then they use that shape's measurements and properties to solve practical problems. | G.MG.A.1 |
Apply concepts of density based on area and volume in modeling situations High School | Students use density to solve real-world problems, like figuring out how many people fit in a room or how much a slab of material weighs based on its size. | G.MG.A.2 |
Apply geometric methods to solve design problems High School | Students use shapes, measurements, and geometric reasoning to solve real-world design problems, like figuring out how much material a structure needs or whether an object will fit in a given space. | G.MG.A.3 |
Use dimensional analysis for unit conversions to confirm that expressions and… High School | Students check that an equation makes sense by tracking units the way they track numbers. If the units don't work out, the math is wrong. | G.MG.A.4 |