Kingston University graduate Fern Toynton has innovated self-assembly furniture and toys with her "Inflate" kit, which uses sausage-shaped party balloons as the primary means of construction. The kit includes beechwood slats with pre-cut holes, designed to be secured by inflating colorful modeling balloons through these holes to form flexible, nail-and-screw-free joints. Toynton, a product and furniture design alum, emphasizes the playful aspects of both the assembly process and the final product, aiming to make the construction engaging and conducive to teamwork among children. This method not only reduces screen time but also fosters creativity by allowing children and their families to explore various non-load-bearing furniture possibilities. The kit comes with an instruction manual that encourages experimental building, leveraging the inherent flexibility and temporary nature of the balloon joints to engage children in creative play.

https://www.dezeen.com/2017/07/30/balloons-replace-nails-screws-for-inflate-childrens-furniture-collection-design-graduate/

Dutch designer Studio Lancelot has developed the "Active Classroom" collection, a series of four innovative stools for primary schools, designed to promote frequent changes in seating positions among children. This initiative aims to enhance both muscular diversity and concentration levels by encouraging students to adopt various postures throughout the school day. Each stool is uniquely structured to support multiple sitting positions, requiring active engagement from the children and promoting the use of muscles that remain inactive in traditional seating. This concept, driven by studies showing the health risks of prolonged conventional sitting, has been shortlisted in the workplace design category of the Dezeen Awards 2020. The project is part of a broader research effort by Lancelot, in collaboration with the Free University of Amsterdam and the University of Groningen, to create healthier classroom environments.

https://www.dezeen.com/2020/09/10/school-chairs-active-classroom-design-children-studio-lancelot/

Students from Burg Giebichenstein University of Art and Design in Germany have unveiled a playful children's furniture and lighting collection at Milan, featuring innovative designs like house-shaped beds and stackable lanterns. The collection includes the Woken Up bed, designed as a "theatre" with a fabric-covered pitched roof and built-in toy storage, the Kipp and Clear table with a blackboard and hidden storage, the Make Way! bookshelf with removable sections for creative play, and the On/Off lantern in various sizes and colors. Each piece is crafted to spark children's imagination and interaction through play.

https://www.dezeen.com/2016/04/24/burg-giebichenstein-university-art-design-german-students-children-furniture-milan-design-week/

Designers Damien Ludi and Colin Peillex have ingeniously combined two traditional porch pastimes into the Rocking Knit, a wooden rocking chair that knits a cap as it moves. This eco-friendly invention, part of the Ecole cantonale d’art de Lausanne's Low-Tech Factory workshop, emphasizes simplicity and efficiency by generating a tangible product through minimal energy use. Showcased at Designer’s Saturday in Langenthal, Switzerland, the Rocking Knit offers a unique blend of leisure and productivity, embodying the workshop's goal of merging experience with the creation of a material item.

https://www.thisiscolossal.com/2016/04/a-rocking-chair-that-knits-you-a-hat-as-you-read-the-paper/

Stork is a birdlike seat for work and play.  

Stork was intentionally made to be soft and playful for my newborn nephew, Stone. I wanted to create a casual space where he could play, study, and grow with this furniture. I believe kids should have objects around them that seem whimsical, almost coming out of a storybook, to inspire them to dream bigger. 

The design originally began as a chair meant to transform elementary school classrooms into more free-flowing and collaborative spaces. Today, Stork's can flock together to create casual workspaces in offices, coffee shops, schools, and homes.  

Stork was born from the original question: How would a kid reimagine their learning experience?

https://designawards.core77.com/Furniture-Lighting/92905/Stork-A-birdlike-seat-for-work-and-play

Designed by Hemmo Honkonen, audible chairs are a series of chairs that make different sounds when sat on. The chairs are a study in mechanically produced sound, movement and interaction. Each chair has its own sound that is triggered by sitting down or getting up from the seat.

https://www.hemmohonkonen.com/audible-chairs.html

Designed by Hemmo Honkonen, audible cabinets are a series of cabinets that all make different sounds when opened. The cabinets are a study in mechanically produced sound, movement and interaction. Each cabinet has its own sound that is triggered by opening and closing the doors.

https://www.hemmohonkonen.com/audible-cabinets.html

https://nuggetcomfort.com/products/the-nugget-koala

This furniture system for children draws inspiration from Slavonian domestic and farm animals, transforming them into functional yet imaginative items such as a cow-shaped desk, stools modeled after dogs and cats, a pig-shaped toy chest, and a chicken pencil-box. Designed to evoke the simplicity and imaginative potential of traditional wooden toys, these pieces encourage children's creativity by serving dual roles as both toys and functional furniture. Crafted primarily from the renowned Slavonian oak, this collection not only offers a creative alternative to modern, prescriptive toys but also celebrates and promotes the cultural heritage and natural beauty of the Slavonian region.

https://www.behance.net/gallery/35871067/Avlia-Furniture-System-for-Children

Rigamajig, conceived by Cas Holman as a large-scale building kit for children, encourages imagination, innovation, and collaboration through its collection of wooden planks, wheels, pulleys, and more, designed for free play without the need for tools or instructions. Originating as a pop-up playground for New York City's High Line Park, this award-winning design fosters cooperation and creativity among children, allowing them to bring their ideas to life. 

https://casholman.com/design/rigamajig