Inclusive Design · Case Study

Designing play that doesn't stop when it rains

Seattle rain cut outdoor playtime short, and the indoor alternative left kids with sensory differences playing far less actively than their peers. I interviewed teachers and occupational therapists, observed play indoors and out, and prototyped an interactive 'floor is lava' mat: a light-up surface with hand-sewn sensory blocks the kids place themselves.

User ResearchField ObservationPhysical PrototypingInclusive Design

Role: Research · Concept · Prototyping · Fabrication
Team: With Sabrina Lin, Mishti Dhawan, Nupur Gorkar · HuskyADAPT
Partner: Experimental Education Unit (EEU), Seattle
Timeline: Spring 2023

The four-person project team standing beside their research poster at the HuskyADAPT showcase. — The team at the HuskyADAPT showcase — Sabrina Lin, Arshita Misra, Mishti Dhawan, Nupur Gorkar.

Overview

Weather owned the schedule

Rain cancelled outdoor play routinely, and the indoor alternative wasn’t equivalent.

Indoor play wasn’t built for sensory difference. Neurodivergent students disengaged where non-disabled students kept playing.

Play is how motor, sensory, and social development happens at this age.

How do we give these kids active, physical, social play indoors — on rainy days, on their terms?

Research

I watched before I asked

I interviewed classroom teachers and occupational therapists who work with these children daily, and ran teacher surveys.

I observed indoor and outdoor free play, watching how kids engaged with the space and each other.

An EEU classroom: child-height wooden tables and chairs packed close together, tall windows onto a grey, rain-bare yard. — Indoors on a rain day — limited floor space, little of it for whole-body play.

The EEU's covered outdoor play area: turf mounds and a winding blue path under a roof overhang. — The covered outdoor area works in light rain, not a downpour.

Decision factors

Constraints → choices

Constraint	Choice
Ages 3–4	No screens, no instructions, no reading
Wide range of sensory needs	Many textures, self-selected — never one prescribed input
Motor and cognitive disabilities	Floor-level, whole-body, no fine motor requirement
Indoor classroom, limited space	Rolls up for storage, wipeable, durable
Play is social	Multiple kids on the mat at once, building the space together

Design decisions

The floor is lava

A game, not an instruction

The mat lights up as “lava.” Sensory blocks are the “rocks” — detachable, and the kids choose where to place them.

Concept sketch: a red dotted mat labelled 'lava' (LED strips, colour-changing), with detachable 'rock' blocks made of sensory material like fur that students position themselves. — The concept: LED 'lava', detachable sensory 'rocks' the kids arrange.

Textures the kids choose

Sensory variety is the feature. Kids find their own input instead of being handed one.

Three team members at a workbench testing coloured gel sheets, fabrics, and cardboard. — Testing what reads as lava and what reads as a safe zone.

A layered mat

Wipeable polyethylene on top, lights in the middle, cushioned base. Teachers flagged spills early, so the surface had to clean up fast.

A team member at a whiteboard sketching the mat's cross-section: vinyl, felt, lights, vinyl, carpet. — Working out the layer stack.

Light as feedback

Immediate, non-verbal, legible to a three-year-old.

Wizard of Oz test

We faked all of it first

Cardboard stand-ins for the sensory blocks, each with a real texture. A mat with lights, no sensors. A team member off to the side, triggering the lights by hand.

Four cardboard block stand-ins on a table, each wrapped in a different texture: rounded pins, foam hearts, wound yarn, plastic strips. — Cardboard 'rocks' wrapped in real textures.

A clear polyethylene sheet laid over a grid of green string lights, with three sewn texture cushions placed on top. — Lights under a poly sheet, sewn cushions on top, switched by hand.

The kids invented floor-is-lava on the spot — and fully believed the mat was reacting to them.

The response loop was the thing. Kids didn’t need to be taught; they made up their own rules and played together. We had that signal before writing a line of Arduino code.

Prototype

Arduino, and a lot of sewing

Arduino-driven lights, with the interaction planned around pressure and motion on the mat.

Hand-sewn sensory cushions. I learned to sew for this project and sewed every one.

Modular construction: cushions and mat sections that pack down to the size of a classroom cupboard.

Hands guiding fabric through a Brother sewing machine in a makerspace. — Learning to sew, then sewing every cushion.

Two team members laying out the full white mat fabric over plastic sheeting on a makerspace floor. — Cutting and laying up the full mat.

The finished mat: a clear wipeable top over a lit green LED grid, with rainbow-fur, sherpa, and blue-velvet texture cushions on top. — The finished mat — wipeable top, LED grid, texture cushions.

Impact

Where it landed

10+ classrooms

using the mat

150 children

with neurodivergence and motor and cognitive disabilities

Still in use today

years after the pilot

What I learned

Three things I'd carry forward

Fake the system before you build it

One person switching lights by hand told us more than a working prototype would have.

Watch, don't ask — when your users are three

The interviews framed the problem; the observations defined it.

Fabrication is design work

The sensory range came out of the sewing, not the spec.