I have had people ask me about stuff for day yards and at home environmental stability. My advice is junk. I purchase stuff to make presentations visually appealing, but junk works just as well.
Most important is to make sure it is safe. I don’t use glass or much metal and thoroughly clean anything that could have chemicals or residue. I love pool noodles but you need to monitor to prevent ingestion. Wooden pallets, plastic pallets, old tarps, old buckets or food pans for hanging as overhead noise makers, the possibilities are endless. Visit the junk yard or recycle yards and you will be amazed at what is thrown away.
I used the ball pit balls for their visual appeal but water bottles work just as well.
I buy pool noodles in bulk when Walmart is phasing out the summer stuff.
I love the camping camping blankets (space blankets) as they shine, reflect, and make great noise. They cheaper online than from Walmart.
Most of my fun objects were something that was being thrown away!
Be creative, be safe!