This short video and interactive assessment activity is designed to teach third graders about identifying the properties of squares.

IM Algebra 1, Geometry, and Algebra 2 are problem-based core curricula rooted in content and practice standards to foster learning and achievement for all. Students learn by doing math, solving problems in mathematical and real-world contexts, and constructing arguments using precise language. Teachers can shift their instruction and facilitate student learning with high-leverage routines that guide them in understanding and making connections between concepts and procedures.

IM 9-12 Math, authored by Illustrative Mathematics, is highly rated by EdReports for meeting all expectations across all three review gateways.

Students who struggle in Algebra 1 are more likely to struggle in subsequent math courses and experience more adverse outcomes. The Algebra 1 Extra Support Materials are designed to help students who need additional support in their Algebra 1 course. Each Algebra 1 Extra Support Materials lesson is associated with a lesson in the Algebra 1 course. The intention is that students experience each Algebra 1 Extra Support Materials lesson before its associated Algebra 1 lesson. The Algebra 1 Extra Support Materials lesson helps students learn or remember a skill or concept that is needed to access and find success with the associated Algebra 1 lesson.

If two inscribed angles intercept the same arc, then the angles are equal. Drag the orange points to change the figure.

An interactive applet and associated web page that demonstrate the inscribed angle of a circle - the angle subtended at the periphery by two points on the circle. The applet presents a circle with three points on it that can be dragged. The inscribed angle is shown and demonstrates that it is constant as the vertex is dragged. Links to other related topics such as Thales Theorem. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

This task shows how to inscribe a circle in a triangle using angle bisectors. A companion task, ``Inscribing a circle in a triangle II'' stresses the auxiliary remarkable fact that comes out of this task, namely that the three angle bisectors of triangle ABC all meet in the point O.

This task is primarily for instructive purposes but can be used for assessment as well. Parts (a) and (b) are good applications of geometric constructions using a compass and could be used for assessment purposes but the process is a bit long since there are six triangles which need to be constructed.

This task provides an opportunity for students to apply triangle congruence theorems in an explicit, interesting context.

This problem introduces the circumcenter of a triangle and shows how it can be used to inscribe the triangle in a circle. It also shows that there cannot be more than one circumcenter.

This task focuses on a remarkable fact which comes out of the construction of the inscribed circle in a triangle: the angle bisectors of the three angles of triangle ABC all meet in a point.

This lesson unit is intended to help teachers assess how well students are able to use geometric properties to solve problems. In particular, it will help you identify and help students who have difficulty: decomposing complex shapes into simpler ones in order to solve a problem; bringing together several geometric concepts to solve a problem; and finding the relationship between radii of inscribed and circumscribed circles of right triangles.

An interactive applet and associated web page that demonstrate the relationship of the interior and exterior angles of a polygon. The applet shows an irregular polygon where one vertex is draggable. As it is dragged the interior and exterior angles at that vertex are displayed, and a formula is continuously updated showing that they are supplementary. The tricky part is when the vertex is dragged inside the polygon making it concave. The applet shows how the relationship still holds provided you get the signs of the angles right. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

The lesson starts with a review of basic geometric terms.Angles are defined.There are four types of angles.A right angle measures 90° and forms a square corner. If you were to sit inside a right angle, you would be sitting straight up.An acute angle measures less than 90° and is open less than a right angle. Acute angles have a smaller measurement. Think of them as small and cute. =) If you were sitting inside an acute angle, you would be bent together like a 'V'.An obtuse angle measures more than 90° and is open more than a right angle. Obtuse angles have a larger measurement. If you were to sit inside a obtuse angle, you would be leaning back as if you were lounging in a beach chair by the pool.A straight angle measures exactly 180° and forms a straight line. If you were to sit inside a straight angle, you would actually have to lay down flat on your back.

An interactive applet and associated web page that demonstrate isosceles triangles (two sides the same length). The applet presents a triangle where the user can drag any vertex. As the vertex is dragged the others move automatically to keep the triangle isosceles. The angles are also updated continuously to show that the base angles are always congruent. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

The goal of this task is to provide an opportunity for students to apply a wide range of ideas from geometry and algebra in order to show that a given quadrilateral is a rectangle. Creativity will be essential here as the only given information is the Cartesian coordinates of the quadrilateral's vertices. Using this information to show that the four angles are right angles will require some auxiliary constructions. Students will need ample time and, for some of the methods provided below, guidance. The reward of going through this task thoroughly should justify the effort because it provides students an opportunity to see multiple geometric and algebraic constructions unified to achieve a common purpose.

This task is closely related to very important material about similarity and ratios in geometry.

The purpose of the module, A Sense of Wonder, is to encourage students to use inquisitive and persistent behaviors as they wonder about their world. The module extends the strategies introduced in prekindergarten. These strategies include using questions to approach problems and identifying attributes to sort, classify, and make inferences. The attribute strategies serve as the foundation for subsequent Grade One and Grade Two Primary Talent Development (PTD) modules. This module is meant for all students. The classroom teacher should work with a specialist or special educator to find or develop alternate activities or resources for visually impaired students, where appropriate.

Students learn about catapults, including the science and math concepts behind them, as they prepare for the associated activity in which they design, build and test their own catapults. They learn about force, accuracy, precision and angles.

This lesson unit is intended to help you assess how well students are able to: Perform arithmetic operations, including those involving whole-number exponents, recognizing and applying the conventional order of operations; Write and evaluate numerical expressions from diagrammatic representations and be able to identify equivalent expressions; apply the distributive and commutative properties appropriately; and use the method for finding areas of compound rectangles.

Students explore in detail how the Romans built aqueducts using arches—and the geometry involved in doing so. Building on what they learned in the associated lesson about how innovative Roman arches enabled the creation of magnificent structures such as aqueducts, students use trigonometry to complete worksheet problem calculations to determine semicircular arch construction details using trapezoidal-shaped and cube-shaped blocks. Then student groups use hot glue and half-inch wooden cube blocks to build model aqueducts, doing all the calculations to design and build the arches necessary to support a water-carrying channel over a three-foot span. They calculate the slope of the small-sized aqueduct based on what was typical for Roman aqueducts at the time, aiming to construct the ideal slope over a specified distance in order to achieve a water flow that is not spilling over or stagnant. They test their model aqueducts with water and then reflect on their performance.

In addition to the purely geometric and trigonometric aspects of the task, this problem asks students to model phenomena on the surface of the earth.