Toy Box
Build a custom toy box for your child's playhouse. Any type of wood will work as long as it is flat and thin, such as plywood, but thick enough to hold nails. You will need two hinges for the back of the toy box lid and a latch or magnets to place on the front of the lid, to close it. Measure and cut six pieces of wood for the four sides, the bottom and the lid. Sand each piece well. Starting with the bottom piece, nail the four sides securely to the bottom and to each other. Add the lid using the two hinges and latch or magnets. If the toy box is not sturdy enough, add four metal brackets along each bottom corner. Paint the box your child's favorite color, then have her decorate the lid with stickers, wall decals or stencils.
Arm Chair
Create a child's version of a standard piece of furniture. Use wood that is at least 3/4 of an inch thick to make sure the chair is sturdy enough to sustain the weight of your child. Pine is a good wood for staining or painting when completed. You will need enough wood to cut a back (11 1/4 inches by 15 1/4 inches), two sides (11 1/4 by 14 1/2 inches), two cleats (1 3/4 inches by 6 1/2 inches) and two arm rests (3 1/5 inches by 15 inches). You may wish to round out the bottom of the back and sides, to give the appearance of legs. Add a slightly rounded curve to the armrests so there are no sharp edges.
Begin by securing the cleats to the sides so you will have solid pieces to attach the back and seat to. Complete by nailing or screwing on the armrests and adding a coat of stain and varnish or paint. As with the toy box, seek you child's input for paint color. You can also have her pick out a seat cushion.
Bookshelf
A bookshelf will help your little one organize her treasures. Measure an area in the playhouse where a bookshelf will fit without being obtrusive. Cut a square piece of board for the back. You can use either plywood or a section of wood paneling for the back. Build a frame from pine wood boards and attach to the back. Decide how many shelves you would like to insert into your box, then measure and cut additional pieces of the pine wood to fit. Secure with nails or screws and finish with a paint color of your child's choice. Using wall brackets, attach the bookshelf to your specified wall area. Let your child decide how she will arrange her treasures on the shelves.