TeachBench - Evaluating LLM Teaching Ability

Created: 2026-05-08 | Tags: llmbenchmarkformative-assessmentpersonalized-learningfeedback-loop
๐Ÿ“„ Full text: arXiv:2601.21375 ยท local
Syllabus-grounded framework for measuring LLM teaching capability via student performance improvement after multi-turn instruction.

The Gap in LLM Evaluation

Li et al. (2026) address a critical gap: while LLMs are increasingly used as teaching assistants, their teaching capability remains insufficiently evaluated.

Limitations of Existing Benchmarks

Benchmark Type Focus Limitation
Problem-solving (MMLU, HELM, GSM8K) Answer correctness Measures solver, not teacher
Exam-centric (AGIEval, C-Eval, GAOKAO-Bench) Exam performance Still solution-centric
Tutoring dialogues (MathDial, TutorBench) Per-turn response quality Misses end-to-end teaching effectiveness

TeachBench shifts the evaluation target: from solving to teaching.

Syllabus-Grounded Framework

Core Design Principles

1. Knowledge-centered: Evaluation based on structured knowledge points (syllabus), not target questions 2. Leakage-controlled: Teacher agents restricted to knowledge points + example problems (no access to test items) 3. Outcome-based: Teaching effectiveness measured by student agent's performance improvement

Workflow


Syllabus โ†’ Knowledge Tree โ†’ Teacher Agent (multi-turn instruction) โ†’ Student Agent โ†’ Performance Gain

Key Findings from Gaokao Experiments

Using Chinese National College Entrance Examination (Gaokao) data across multiple subjects:

Finding Implication
Domain variation: Math teaching effective (7.63pt gain with Qwen3-235B), but physics/chemistry challenging Teaching ability is domain-specific, not generalized
Example problems backfire: Models shift to error correction vs. syllabus-grounded instruction Current LLMs struggle with structured teaching vs. reactive problem-solving
Teaching โ‰  Solving: Models good at solving aren't necessarily good at teaching Teaching ability is a distinct LLM behavior dimension

Connection to Existing Work

vs. AI Tutor Effectiveness

vs. Educational LLM Alignment

vs. Agentic Workflows

Implications for AI in Education

For LLM Development

For ITS Design

For Benchmark Design

Related Pages

Sources