Simple and Quick Children's Headboard

Measure width of head of mattress.

Take measurment to local lumber yard or garden supply center.

Purchase 3 ft. high Picket Fencing (or enough lumber to assemble your own)
 cut to the width you desire.

   If assembling from scratch: Purchase  1"x3" lumber, cut to 3 ft lengths.
   Saw one end of 3 ft. piece to a point /\.  Nail these 3 ft. pieces to
   2 parallel pieces cut to width of mattress.

For safety, sand points to remove sharp ends.

Paint in latex color of your choice.

Screw into wall or screw into bed frame.