Making brushes out of sticks was a very interesting idea to me as I loved the mixture of the natural world and bringing the two together. we ran a workshop on this subject in the university which I thoroughly loved and it gave me many ideas for sessions that incorporate the outside natural world and the therapeutic process of creating art and the instruments together.
Using found materials to make art pieces such as tools and stencils is a great way to introduce the natural world into the artists repertoire, the variety of textures and shapes are practically limitless.
Cutting cardboard up to make patterns and natural textures and shapes, I found pinecones and seeds particularly interesting as the paint interacted with the cracks and crevices very well.
Forks, cups, patterned clothes, lace, wood, leaves all have incredible potential, the lace can be used to adopt a stencil-like an approach to overlay and add depth to the artwork.
https://www.messylittlemonster.com/2015/07/stick-craft-nature-paintbrushes.html https://www.applegreencottage.com/2016/03/DIY-nature-paint-brushes-kids.html
Make your own Nature Paintbrushes – Painting with flowers and nature ..
https://lynnechapman.blogspot.com/2017/03/mark-making-exploration.html