Is Goblins free for teachers?

Yes. Goblins offers a generous free tier that includes 1 live feedback assignment per week, insights on student mastery and replays, and the ability to upload your own content. The Max plan adds unlimited assignments, superadaptive mode, grade exports, standards growth reports, and SSO/LMS integration, with per-student pricing for schools and districts.

How does Goblins work?

Three simple steps: (1) Share an assignment from thousands of standards-aligned topics using a share code. (2) Students speak and draw their thinking naturally, and Goblins responds with Socratic questioning that sounds just like their teacher. (3) Teachers get real-time formative insights showing what students struggle with and suggestions to inform instruction.

Does Goblins prevent cheating?

Yes. Goblins uses a purpose-trained AI model that evaluates cheating signals in real time. It can detect when students are copying answers, using external tools inappropriately, or not genuinely working through problems. Copy-pasting answers is also blocked.

Can I use my own voice with Goblins?

Yes. Teachers can record their voice and take a selfie to create a custom 3D avatar in about 30 seconds. Students then hear help in their own teacher's voice and see a familiar face, making the experience more personal and effective.

What math levels does Goblins cover?

Goblins covers math from Grade 5 through AP Calculus, including thousands of standards-aligned topics. Teachers can also upload their own content for custom assignments at any level.

Is Goblins FERPA compliant?

Yes. Goblins is FERPA and state compliant. Student data privacy and security are a top priority.

Does Goblins support English Language Learners?

Yes. Goblins supports 30+ languages so teachers don't have to translate every worksheet. It is especially helpful for ELL students who need accessible math instruction in their native language.

What grade level is G-SRT taught?

This standard is part of the G-SRT curriculum in Mississippi College- and Career-Readiness Standards for Mathematics.

G-SRT: Geometry: Similarity, Right Triangles, and Trigonometry (G-SRT)

Geometry: Similarity, Right Triangles, and Trigonometry (G-SRT)

Print

G-SRT.1Verify experimentally the properties of dilations given by a center and a scale factor:G-SRT.10Prove the Laws of Sines and Cosines and use them to solve problems.G-SRT.11Understand and apply the Law of Sines and the Law of Cosines to find unknown measurements in right and non-right triangles (e.g., surveying problems, resultant forces).G-SRT.2Given two figures, use the definition of similarity in terms of similarity transformations to decide if they are similar; explain using similarity transformations the meaning of similarity for triangles as the equality of all corresponding pairs of angles and the proportionality of all corresponding pairs of sides.G-SRT.3Use the properties of similarity transformations to establish the AA criterion for two triangles to be similar.G-SRT.4Prove theorems about triangles. Theorems include: a line parallel to one side of a triangle divides the other two proportionally, and conversely; the Pythagorean Theorem proved using triangle similarity.G-SRT.5Use congruence and similarity criteria for triangles to solve problems and to prove relationships in geometric figures.G-SRT.6Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.G-SRT.7Explain and use the relationship between the sine and cosine of complementary angles.G-SRT.8Use trigonometric ratios and the Pythagorean Theorem to solve right triangles in applied problems.G-SRT.9Derive the formula A = ½ ab sin(C) for the area of a triangle by drawing an auxiliary line from a vertex perpendicular to the opposite side.

Example Problems

Polygon Y has an area of 11 square units. Celia drew a scaled version of Polygon Y using a scale factor of 3 and labeled it Polygon Z.
What is the area of Polygon Z?

Polygon H is a scaled copy of Polygon F using a scale factor of

\frac{1}{4}

.
Polygon H's area is what fraction of Polygon F's area?

Express

z_1 = 18(\cos(4\pi/3) + i\sin(4\pi/3))

in rectangular form.
Express your answer in exact terms.

1-on-1 AI tutoring aligned to G-SRT. Instant help for students, real-time insights for teachers.

Used in classrooms by 100,000+ students at Baltimore County, Plano ISD, Deer Valley USD, KIPP, and districts nationwide.

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