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-GMD taught?

This standard is part of the G-GMD curriculum in Alaska Mathematics Standards.

G-GMD: Geometric Measurement and Dimension

Geometric Measurement and Dimension

Print

Geometric Measurement and Dimension covers volume formulas for cylinders, pyramids, cones, and spheres, with informal justifications using Cavalieri's principle. Cross-sections of three-dimensional figures and solids of revolution connect two- and three-dimensional geometry. The work builds fluency in applying formulas while developing spatial reasoning about three-dimensional shapes.

G-GMD.1Explain how to find the formulas for the circumference of a circle, area of a circle, volume of a cylinder, pyramid, and cone.G-GMD.2(+) Give an informal argument using Cavalieri’s principle for the formulas for the volume of a sphere and other solid figures.G-GMD.3Use volume formulas for cylinders, pyramids, cones, and spheres to solve problems. For example: Solve problems requiring determination of a dimension not given.G-GMD.4Identify the shapes of two-dimensional cross-sections of three-dimensional objects, and identify three-dimensional objects generated by rotations of two-dimensional objects.

Example Problems

Find the area of a circle with a radius of

3 \text{ cm}

.
Either enter an exact answer in terms of

\pi

or use

3.14

for

\pi

and enter your answer as a decimal.

A hexagonal pyramid has a volume of

300 \text{ cm}^3

and a height of

20 \text{ cm}

.
What is the area of the base of the pyramid?

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