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.

AFM.13

Use the recursive process and difference equations to create fractals, population growth models, sequences, and series.

Example Problems

Given the following recursive formula for the sequence:

f(1) = 0

and

f(n) = f(n - 1) + n

What is

f(2)

Given the following recursive formula for the sequence:

f(1) = 2

and

f(n) = f(n - 1) + n

What is

f(2)

Given the following recursive formula for the sequence:

f(1) = -1

and

f(n) = f(n - 1) \cdot 6

What is

f(3)

Khan Academy Resources

Intro to arithmetic sequences Intro to arithmetic sequence formulas Arithmetic sequences review Explicit formulas for arithmetic sequences Converting recursive & explicit forms of arithmetic sequences Recursive formulas for arithmetic sequences Warmup: exponential vs. linear growth Use arithmetic sequence formulas Extend geometric sequences Use geometric sequence formulas Extend arithmetic sequences Recursive formulas for arithmetic sequences Exponential growth vs. decay Converting recursive & explicit forms of arithmetic sequences Graphing exponential growth & decay Recursive formulas for geometric sequences Evaluate sequences in recursive form Explicit formulas for geometric sequences Graphs of exponential growth Converting recursive & explicit forms of geometric sequences Exponential vs. linear models Sequences word problems Explicit formulas for arithmetic sequences Exponential vs. linear growth over time Linear vs. exponential growth: from data Intro to arithmetic sequences Sequences intro Intro to geometric sequences Arithmetic sequence problem Explicit & recursive formulas for geometric sequences Graphing exponential growth & decay Converting recursive & explicit forms of arithmetic sequences Graphs of exponential growth Sequences word problems Linear vs. exponential growth: from data Exponential decay intro Exponential vs. linear models: verbal Converting recursive & explicit forms of geometric sequences Modeling with basic exponential functions word problem Linear vs. exponential growth: from data (example 2)Explicit formulas for arithmetic sequences Recursive formulas for arithmetic sequences

1-on-1 AI tutoring aligned to AFM.13. 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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