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.

A1.37

Describe events as subsets of a sample space (the set of outcomes) using characteristics (or categories) of the outcomes, or as unions, intersections, or complements of other events ("or," "and," "not").

Example Problems

Let

X = \{1, 3, 5\}

and

Y = \{2, 3, 4\}

.
What is

X \cup Y

?

Let

X = \{7, 14, 21\}

and

Y = \{14, 28\}

.
What is

X \cup Y

?

Let

X = \{2, 5, 10\}

and

Y = \{1, 2, 3, 5\}

.
What is

X \cap Y

?

Khan Academy Resources

Permutations Combinations Probability with permutations and combinations Interpret probabilities of compound events Probability with general multiplication rule Dependent probability introduction Probability with Venn diagrams Addition rule for probability Compound probability of independent events Probability using combinations Independent events example: test taking Ways to arrange colors Ways to pick officers Combination example: 9 card hands Example: Lottery probability Example: Different ways to pick officers Mega millions jackpot probability Probability with combinations example: choosing groups Permutation formula Combination formula Probability with permutations & combinations example: taste testing Possible three letter words Handshaking combinations Probability with combinations example: choosing cards Factorial and counting seat arrangements Interpreting general multiplication rule General multiplication rule example: dependent events Zero factorial or 0!Intro to combinations

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