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.

AFA.FGR.3.9

Create, apply, and interpret piecewise functions in real-world financial applications.

Example Problems

Find

f(-10)

for the piecewise function

f(x)

f(x) = \begin{cases} 3x + 4 & , & x < -8 \\ x^2 + 2x - 1 & , & -8 \leq x < 5 \\ 11 - x & , & x \geq 5 \end{cases}

Find

f(5)

for the piecewise function

f(x)

f(x) = \begin{cases} \frac{1}{x - 6} & , & x = 2 \\ -(x - 1)^2 & , & x = 9 \\ 4x - 3 & , & x \neq \{2, 9\} \end{cases}

Find

f(18)

for the piecewise function

f(x)

f(x) = \begin{cases} \sqrt{18x} & , & x = 18 \\ \frac{-36}{x} & , & x = 23 \\ 25 - x & , & x \neq \{18, 23\} \end{cases}

Khan Academy Resources

Interpret quadratic models Comparing linear functions word problems Linear models word problems Exponential vs. linear models Piecewise functions graphs Sequences word problems Exponential expressions word problems (numerical)Exponential vs. linear growth over time Construct exponential models Evaluate piecewise functions Linear vs. exponential growth: from data Interpret exponential expressions word problems Modeling with sinusoidal functions Intro to exponential functions Constructing exponential models: percent change Trig word problem: modeling annual temperature Constructing exponential models: half life Interpret quadratic models: Factored form Worked example: graphing piecewise functions Comparing linear functions word problem: climb Sequences word problems Linear vs. exponential growth: from data Exponential expressions word problems (numerical)Worked example: evaluating piecewise functions Comparing maximum points of quadratic functions Introduction to piecewise functions Exponential vs. linear models: verbal Worked examples: Forms & features of quadratic functions Comparing features of quadratic functions Worked example: domain & range of piecewise linear functions Interpret quadratic models: Vertex form Constructing exponential models Worked example: domain & range of step function Trig word problem: modeling daily temperature Modeling with basic exponential functions word problem Linear vs. exponential growth: from data (example 2)Exponential expressions word problems (algebraic)Graph interpretation word problem: basketball

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