Homework and AI: keep the practice, not just the answers

[ HOMEWORK ]

Homework scores up, test scores down

The clearest everyday-use evidence comes from homework. In a 30-month study of 26,811 Chinese students in grades 7-12, adopting AI raised homework scores 18% and cut monthly closed-book exam scores 20% within six months; students who kept spending normal time on homework lost little. Time per assignment fell from 64 to 45 minutes, and losses grew with self-reported hours of AI use. It is a working paper and not randomized, but it matches the randomized evidence: answer-giving AI raised practice scores 48% and cut unaided exam scores 17% in a high-school field experiment.

What students say

10% of teens do all or most of their schoolwork with chatbot help (Pew Research Center, Feb 2026). 63% of teens who use AI for schoolwork get answers from it, and 39% feel they miss out on learning. Yet most still start on their own: when stuck on schoolwork, 65% of teens first try on their own or ask a person, and 10% go to AI first (Common Sense Media, Aug 2026).

Design homework for practice

• Retrieval: short questions students answer from memory. Classroom quizzing improves learning, g = 0.50 across 222 studies.
• Spacing: revisit last week's skills in this week's homework. Spaced retrieval beats massed study, g = 0.74 across 29 studies.
• Attempt first: ask for the student's attempt before any help, and say so in the AI rule.
• Short and mixed: a few problems from several skills beats a long set of one kind.

Grade less of it, check more of it

If homework is practice, grading every answer rewards whoever got the most help. Give feedback on homework, and grade short unaided checks in class instead. That keeps the incentive on the skill rather than the answer.

Set the AI rule for each assignment

Put the AI level on every assignment: no AI, AI for hints and feedback, AI with disclosure, or AI as part of the task. In Nexus, each class has a learning mode that students cannot change, so a Hints class keeps homework help to hints whatever device the student uses at home.

Make the process visible

Ask for a two-line reflection with AI-assisted homework: the question the student asked, and one thing they can now do without help. Class chats in Nexus show teachers how a student worked, and students are told when a chat can be reviewed.

Talk with families

Parents are mostly open to AI for schoolwork: about 60% are comfortable with teens using chatbots for schoolwork (Pew Research Center, Feb 2026), and 57% of high school parents say using generative AI for schoolwork is better than not using it (College Board). Tell them what the homework rule is and why. Our parent letter template helps.