Design a vending machine for school children (ages 6–12)

Design a smart, healthy vending machine specifically tailored for elementary and middle school children (ages 6–12) located in school cafeterias.

Context

Traditional vending machines are physically too tall for young kids, feature confusing numeric keypads, vend unhealthy snacks, and swallow cash coins.

Clarifying questions to ask first

How is payment handled (cash, school ID card, or free government lunch program)?
Are there school district dietary guidelines to enforce?

How to approach it

Analyze Target Users & Ergonomics: Children ages 6-12 (varying heights 3.5ft - 5ft), cognitive reading levels, tactile exploration vs Parent/School Nutritional Administrators
Identify Key Pain Points: Cannot reach top snack buttons or coin slots, allergic reactions from hidden ingredients, losing lunch money, jammed spirals
Design Accessible & Engaging Solutions: Lowered touchscreen with visual pictorial icons, RFID wristband / Student ID card tap linked to parent prepaid lunch balance, Allergen Lockout System (automatically hides peanut/dairy snacks for allergic kids), Gamified healthy choice reward tokens
Define safety, durability, and health success metrics

Framework: User Group Segmentation (Kids, Parents, School) -> Physical & Cognitive Pain Points -> Hardware & Software Solutions -> Prioritization & Guardrails

Sample answer

Physical height is the #1 physical blocker: interactive display and dispensing tray must be located below 3 feet
Allergy safety is critical: scan student badge to filter out allergens in real-time

MVP: Ruggedized low-height vending kiosk with visual touchscreen, RFID school lunch badge tap, real-time dietary allergen filtering, and optical anti-drop jam sensors

Executive design: An accessible, low-height smart vending kiosk with RFID school badge payments, automated allergen filtering, and gamified rewards for nutritious snack choices.

What interviewers look for

Ergonomic & Physical Height Accommodation
Child-Friendly Visual UI / Allergy Safety
Parental Control & Cashless Payment Integration
Tamper & Safety Engineering