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 5.M.3 taught?

This standard is part of the Grade 5 curriculum in Indiana Academic Standards - Mathematics.

Are there practice problems for 5.M.3?

Yes, there are 3 practice problems available for 5.M.3 with worked examples.

What learning resources are available for 5.M.3?

There are 18 Khan Academy resources available for 5.M.3, including 7 videos, 9 exercises, 2 articles.

5.M.3: Develop and use formulas for the area of triangles, parallelograms, and trapezoids. Solve real-world and other mathematical problems that in... | Indiana Academic Standards - Mathematics

Develop and use formulas for the area of triangles, parallelograms, and trapezoids. Solve real-world and other mathematical problems that involve perimeter and area of triangles, parallelograms, and trapezoids, using appropriate units for measures. (E)

Example Problems

A bird feeder roof is a square pyramid with a base edge of

0.5 \text{ m}

and a slant height of

0.75 \text{ m}

. The underside of the roof (the base) will also be painted.

What is the total painted area?

A ceramic decorative pyramid has a base edge of

14 \text{ cm}

and a slant height of

10 \text{ cm}

. The glazing will cover the entire outside, including the base.

How much glazed surface area is needed?

A hollow model of a square pyramid has a base edge of

20 \text{ cm}

and a slant height of

25 \text{ cm}

. The cardboard used includes the base.

What is the total area of cardboard needed?

Khan Academy Resources

Area of parallelograms Area of triangles Area of parallelograms Area of triangles Find missing length when given area of a triangle Area of right triangles Find missing length when given area of a parallelogram Area of rectangles with fraction side lengths Decompose area with triangles Area of composite shapes Find base and height on a triangle Area of a triangle Finding area by rearranging parts Area of a parallelogram Area of composite shapes Finding area with fractional sides 1 Finding area with fractional sides 2 Area of quadrilateral with 2 parallel sides

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5.M.3: Develop and use formulas for the area of triangles, parallelograms, and trapezoids. Solve real-world and other mathematical problems that involve perimeter and area of triangles, parallelograms, and trapezoids, using appropriate units for measures. (E)