My son has a bloody scab & thick, yellow mucus in his nose. He has a scab on the corner of his mouth & red spots on his face as well. Any ideas?

Impetigo. Have him checked for proper treatment.
Impetigo. Your son likely has an infection called Impetigo caused by Streptoccocus or Staph. It is fairly easily treated with antibiotics. It is very contagious so make sure you practice good had washing and no sharing of towels. Get him in to be seen.
Impetigo. The most likely thing would be impetigo, or infected skin sores. Once there is a break in the skin, from scratching or other irritation, it is easy for the bacteria to spread. Since children keep their hands in their mouth, nose and around their face, the infection can spread quickly. Talk to your doctor about using an antibiotic ointment.