At the link are the free plans to build this modern platform bed. Build this platform bed and slatted headboard or make just one of them.
This step-by-step is for a king sized platform bed, but you could adjust the size for something smaller.
Make a teen platform bed with storage that is easy to build and maximizes material usage. This bed combines style and storage. At a low platform height, it can be the perfect lounge spot for your teen. Sized for queen mattress.