EcoThreads is a sustainable e-textile prototyping approach that fabricates biodegradable functional threads using two methods: wet spinning and thread coating. The approach aims to address the environmental impact of rapid e-textile prototyping by incorporating biodegradable materials into e-textile practices. The wet spinning method involves dissolving polymers in a solvent and extruding the filament into a cross-linking agent to form the fiber. A modified DIY syringe pump is used to spin biodegradable conductive threads. The thread coating method involves coating conductive dispersion onto natural fibers. Conductive and interactive threads can be integrated into textiles through weaving, knitting, and embroidery. The EcoThreads approach provides a sustainable life cycle for e-textile prototyping, allowing individual creators to incorporate biodegradable materials. The workshop study with e-textile practitioners demonstrated the compatibility of EcoThreads with existing e-textile practices. Participants created various e-textile applications, including biodegradable e-textile swatches, disposable LED patches, pH-sensing picnic blankets, stretch sensors, and heated pockets. The study highlighted the compatibility of EcoThreads with existing e-textile practices, the challenge of sourcing materials, and the preference for specific conductive threads. The EcoThreads approach offers a sustainable and accessible method for e-textile prototyping, enabling the creation of biodegradable e-textiles with tunable conductive and interactive properties.EcoThreads is a sustainable e-textile prototyping approach that fabricates biodegradable functional threads using two methods: wet spinning and thread coating. The approach aims to address the environmental impact of rapid e-textile prototyping by incorporating biodegradable materials into e-textile practices. The wet spinning method involves dissolving polymers in a solvent and extruding the filament into a cross-linking agent to form the fiber. A modified DIY syringe pump is used to spin biodegradable conductive threads. The thread coating method involves coating conductive dispersion onto natural fibers. Conductive and interactive threads can be integrated into textiles through weaving, knitting, and embroidery. The EcoThreads approach provides a sustainable life cycle for e-textile prototyping, allowing individual creators to incorporate biodegradable materials. The workshop study with e-textile practitioners demonstrated the compatibility of EcoThreads with existing e-textile practices. Participants created various e-textile applications, including biodegradable e-textile swatches, disposable LED patches, pH-sensing picnic blankets, stretch sensors, and heated pockets. The study highlighted the compatibility of EcoThreads with existing e-textile practices, the challenge of sourcing materials, and the preference for specific conductive threads. The EcoThreads approach offers a sustainable and accessible method for e-textile prototyping, enabling the creation of biodegradable e-textiles with tunable conductive and interactive properties.