Welcome to HCM,
With little history, it seems that your kid might be having impetigo contagiosa
Initially there may be small elevated lesion with infection, then due to healing process, it might convert to scab.
So, do not worry, it may go away in few days without treatment.
Still, you contact dermatologist
for firm diagnosis.
Antibiotic in proper dose and local application of antibiotic cream might improve the condition.
Cleanse the scalp
with mild savlone with water.
I hope you got my answer.
Dr. Ilyas Patel MD