I used an old dresser with good drawers on it and put all of our "educational" materials in there-- one drawer for 'art' materials, her smock, and a dropcloth; one for our dry-erase markers (which work great on windows, too, by the way, and kids find this DELIGHTFUL), pencils, manipulatives (gram cubes-- which are multipurpose and can be used as math sticks, calibrated weights, cm cubes, etc) and our balance, and one for paper and workbooks and more formal "school" stuff.
Later-- during our 'eclectic' phase of homeschooling, I also used a few plastic storage tubs (the smaller size like for shoes) to make theme boxes every few months. One was a fairy-tales box with puppets, scarves, small books, and a few other odds and ends. Other theme boxes included Time, Paper, Measurement, Rocks, and Magnets.
Bear in mind that my mom was a great resource that most parents don't have here, too-- she had 40y worth of accumulated prek through primary materials and a lot of expertise. She didn't understand gifted kids well, and PG ones not at all, but that is another matter.
LOL.
One of my favorite photos of DD from this time is of her laughing hysterically, dressed in her art smock, blowing bubbles into a solution with food coloring and stabilizer (probably gelatin) on a child-height table perched atop a plastic dropcloth (really a clearance bargain plastic tablecloth). She was SO happy. All it took was a large plastic bowl and a long straw (which, okay-- I cheated and used cellophane tape to MAKE one from two drinking straws). The original plan had been for her to take a sheet of newsprint and "preserve" her bubbles as a nice, marbled print... but she was fascinated by the BUBBLES themselves, and delighted herself for an hour or so with this activity. Long enough that I got the picture, anyway. She was about three.
I also allowed her to 'fingerpaint' with a can of shaving cream on that table, which was a great sensory experience for her.
So my essentials are:
sandtray (but you can easily improvise one with cornmeal and kitchen items from a thrift store)
Child-sized table and chairs
Easel-- ours had one side chalkboard, one side dry-erase board, and a place to attach paper.
child-sized (or at least small) household tools like a broom, etc.
Smock (or old adult teeshirts)
dropcloths (I liked the flannel-backed tablecloths because they were soakproof and nonskid-- plus, after any major holiday, they are also dirt cheap-- my kind of item!)
Painter's tape
a variety of different types of paper, adhesives, and art supplies.
The rest is pretty much all amenable to improvisation once you understand the purpose of the activity/item.
