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SoaPen, a soap-crayon, promotes the habit of washing hands with soap among children of the impressionable age of 3-6 years. We aim to reduce child mortality rates by preventing the spread of infectious illnesses through behavioral change.

  • Product shot 1

  • SoaPen: Make Handwashing a Habit

    SoaPen: Make Handwashing a Habit

  • The very first rendering

  • Initial general sketches & models

  • Sensor ideation sketches

  • SoaPen assembly

What it does

SoaPen, a soap-crayon, promotes the habit of washing hands with soap among children of the impressionable age of 3-6 years. We aim to reduce child mortality rates by preventing the spread of infectious illnesses through behavioral change.

Your inspiration

While pursuing a BFA in Product Design together, our shared belief in the potential of good design driving change impelled us to enter ‘Wearables for Good Challenge’ by UNICEF. which called for designers to address problems the world was facing. We were inspired by the realization that more than half of over 1.5 million children under 5 dying annually from infectious diseases, can be saved by the simple act of handwashing at key times daily. Our desire to address this grave issue by promoting good handwashing habits while adding a little fun to the solution, led to SoaPen.

How it works

SoaPen is a soap-crayon. Being markable on skin, it is used for drawing on a child’s dry hands. When children wet and rub their hands, the drawing lathers, and prompts them to wash their hands for the ideal 20-40 seconds. Teachers can apply SoaPen to a child's hands within the classroom and effortlessly ensure the desired level of sanitation by checking, after the hand wash, that the child’s hands are mark free. A supporting website provides ideas to incorporate SoaPen into the curriculum, downloadable posters, etc. to reach far & wide. SoaPen taps into a two-directional awareness flow: Children learn how to wash their hands in schools, take their knowledge home and share it with parents. It fulfills the 3 “R”s of habit formation: Reminder: the physical presence of SoaPen in the classroom; Routine: the SoaPen website suggests innovative ways of using SoaPen daily; Reward: joy of unmarked hands.

Design process

We submitted a sketch of a soap crayon wrapped with paper to the Wearables for Good Challenge in August’15. During our mentorship later, we pushed the design to examine all angles of usage: the user, application and placement. We went through various rounds of ideation from keeping it as simple as a crayon to having multiple sensors in the casing. The team brainstormed on putting a reward system in place to inspire usage, like perhaps a toy embedded at the end of the soap refill. In the end, we chose to keep SoaPen in its most effective form: a soap crayon with a plastic casing and push up mechanism for easy usage. We detailed every facet of the pen, including the shape. We moved away from the initial circular prototype to a triangular form. Our evaluation in schools showed that children hate drawing with a blunt tip, the cylindrical crayon also rolled off the teacher’s table and had the potential to break. The triangular pen tackled both these problems by allowing flat resting sides and 3 pointed tips for children to draw with. It can also be stacked allowing for efficient flat-packed shipping. Attention to detail and user feedback continues to dictate and push our prototypes.

How it is different

Despite some amount of awareness and access to soap, low-income urban people lack awareness of hygienic habits like handwashing. There is a shortfall in the product form and placement that reaches them. SoaPen, placed in a classroom, allows the teacher to monitor children using the soap, preventing wastage and ensuring regular use. Unlike normal soap which the child washes off in 2-4 seconds; SoaPen ensures the child spends 20-40 seconds removing all marks which is the ideal duration of handwashing. Children enjoy the activity of turning their drawings into soap, and thus follow up with the teacher to make sure s/he makes them wash their hands regularly. The website proposes activities and posters in the classroom making SoaPen a part of the everyday schedule. Unlike a campaign led by a health worker which requires repeated human invested visits, SoaPen and its impact will sustain itself after an initial introduction!

Future plans

SoaPen is nearing the manufacturing stage. Its biggest strength lies in awareness & habit formation. Projecting the increase in internet penetration among low-income rural and urban communities, we hope our website will help train teachers about the importance of handwashing with soap even in the absence of health workers. The simple design is scalable and low-cost. The materials and manufacturing techniques can be localized for materials and resources allowing the product to reach as many hands as fast as possible. We want SoaPen to be recreated everywhere to help promote good hygiene through handwashing in communities across the globe.


Recently won the UNICEF Wearables for Good challenge powered by UNICEF, ARM and frog. Presented at the Global Health International Conference at Yale University Invited to the Global Entrepreneur Summit hosted by Barack Obama at Stanford.

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