Hi! LEGO Education has recently uploaded a bunch of free lesson plans around making/rapid prototyping with LEGO. The lesson plans are aligned with products, but you can customize them to use with any collection of LEGO you have on hand. They have a Wearables lesson plan and it gives students inspiration on types of wearables to make and encourages thinking on why to make one. You can also use anything to prototype making a wearable, and then use low or high tech electronics to make your invention come to life. I have taught this lesson using basic LEGO + mixed media, WeDo 2.0, Mindstorms, and with LEGO Simple and Motorized Machines and Mechanisms. The inventions have ranged in scale from spinning corsages to talking and sensing walking sticks for the blind.
Here's the link to the LEGO Edu lesson plan:
https://education.lego.com/en-us/lessons/maker-middleschool/wearables