Greenhouses. Ziplock bag, wet cotton balls and seeds. You can see all the plant parts. This has a printable for the "house". Although I think I might just tape the bags to the window and have a lot of them.
Learning Shapes With Toy Cars. Create your own shaped road tracks using black sandpaper. Teach your toddler or preschooler their shapes with a triangle, square, circle, rectangle, pentagon and octagon road track.