Share 'Toddler Boys Room'

I need help. My son, 2, is ready for his big boy room. I am looking for cheap ideas. We have some wall art that was bought at Goodwill or given to us as gifts from the Grandpop. I am doing a construction theme. He loves trucks, diggers, fork lifts etc. He is a fanatic about race cars & it helps that daddy is a race car driver. So any advice would be so appreciated.