Setting up an open-ended, process-based activity like this is a great way to encourage curiosity, creativity and exploration through undirected sensory play.
What you need:
Paper
Paint and other mark making materials
(Top Tip: use non-toxic, washable mark making materials)
As a child, I loved playing with the little circular plastic ball mazes that I found in Christmas crackers and party gift bags.
I now know that playing with ball mazes develops hand-eye co-ordination and that making them is a great STEM activity promoting the development of a number of skills including designing, constructing, problem-solving, ...
Getting your kids to design, make and test their own boats keeps them busy and promotes the development of fine motor, creative and language skills, scientific understanding and problem solving.
What you need:
(This is just a suggested list of resources, you do not need everything on it. Add your own ...
Getting your kids to design, and make, their own musical instruments keeps them busy and promotes the development of fine motor, creative and language skills and scientific understanding.