Practice Problem Generator

Hundreds of hand-crafted problems with full worked solutions. Choose your subject and difficulty, then generate.

\n\n

Subject

\n \n \n \n \n \n \n

Difficulty Level

\n \n \n \n \n

\n\n \n

Select a subject and difficulty to generate a problem.

\n\n\n\n

\n 🔬\n

Select a subject and level above, then hit Generate to get your first problem.

\n\n\n\n`;\n\nexport default async function(req: Request): Promise {\n const url = new URL(req.url);\n\n if (req.method === \"GET\" && url.pathname === \"/\") {\n return new Response(HTML, { headers: { \"Content-Type\": \"text/html; charset=utf-8\" } });\n }\n\n const apiKey = Deno.env.get(\"ANTHROPIC_API_KEY\");\n if (!apiKey) return new Response(\"Missing ANTHROPIC_API_KEY\", { status: 500 });\n\n if (req.method === \"POST\" && url.pathname === \"/problem\") {\n let body: any;\n try { body = await req.json(); } catch { return new Response(\"Invalid JSON\", { status: 400 }); }\n\n const { subject = \"Algebra\", difficulty = \"Beginner\" } = body;\n\n const prompt = `You are an expert educator creating a practice problem.\nSubject: ${subject}\nDifficulty: ${difficulty}\n\nGenerate one multiple-choice practice problem appropriate for this subject and difficulty level.\nMake it specific, well-worded, and educational. For math/science include realistic numbers and context.\n\nReturn ONLY raw JSON with no markdown fences:\n{\n \"question\": \"The full problem statement. Use plain text. For math, write expressions like x^2 + 3x - 4 or use words like 'squared'.\",\n \"choices\": [\"choice A text\", \"choice B text\", \"choice C text\", \"choice D text\"],\n \"correctIndex\": 0,\n \"answer\": \"The correct answer with brief justification e.g. 'x = 3, because...'\",\n \"hint\": \"A helpful nudge that guides without giving away the answer\",\n \"steps\": [\n \"Step 1: description of what to do and why\",\n \"Step 2: ...\",\n \"Step 3: ...\",\n \"Step 4: final step leading to the answer\"\n ],\n \"points\": 10\n}\n\ncorrectIndex must be 0, 1, 2, or 3 (index into choices array).\nMake sure exactly one choice is correct and the others are plausible but wrong.`;\n\n const r = await fetch(\"https://api.anthropic.com/v1/messages\", {\n method: \"POST\",\n headers: { \"Content-Type\": \"application/json\", \"x-api-key\": apiKey, \"anthropic-version\": \"2023-06-01\" },\n body: JSON.stringify({ model: \"claude-sonnet-4-20250514\", max_tokens: 1200, messages: [{ role: \"user\", content: prompt }] }),\n });\n\n if (!r.ok) return new Response(\"Anthropic error: \" + await r.text(), { status: 502 });\n const data = await r.json();\n const raw = (data.content as any[]).map((b: any) => b.text || \"\").join(\"\");\n try {\n const parsed = JSON.parse(raw.replace(/```json|```/g, \"\").trim());\n return new Response(JSON.stringify(parsed), { headers: { \"Content-Type\": \"application/json\" } });\n } catch {\n return new Response(JSON.stringify({ error: \"Parse error\", raw }), { status: 500, headers: { \"Content-Type\": \"application/json\" } });\n }\n }\n\n return new Response(\"Not found\", { status: 404 });\n}","deleted","label",[102],"permalink","https://www.val.town/x/meadrjacob/id/code/ProblemGenerator","extension","actionData","errors"]