"Cloud" dough is a lovely sensory experience to provide for preschool children. It has a beautiful silky smooth texture and can smell divine… depending on which baby oil you choose to add to the mix. Mix 8 cups of plain flour to 1 cup of baby oil.
Make a backyard bowling alley. Add food coloring to clear plastic bottles of water. Use party streamers as lane margins. Add glow sticks for night bowling. (These would make great outdoor table nightlights also with the glowsticks, gonna try it!
DIY Ball/Foam Pit for kids. Small plastic pool plus cut up pool noodles! Why didn't I think of this? I was just looking at those plastic balls the other day.this is WAY cheaper! Pool noodles at the dollar store!
Newspaper Play Structures -- kids can build & re-build them. Throw a sheet overtop for an instant reading nook. Fine motor for rolling, planning, hand strength to hole punch, sensory hangout if add a blanket.