My son has a spot on his lower tummy that kind of scally any idea what it could be?

Dry, Scaly, Round?: If annular pattern with scaly appearance consider skin fungal infection - may itch but not usually painful. Treatment is topical antifungal, can spread locally. If accompanied by systemic URI symptoms, some viral infections can cause similar rash, typically followed by more disseminated rash all over trunk (pytiriasis). Also consider eczema (itchy), contact dermatitis, cellulitis (red/warm/sprea.

Without exam: Your description is inadequate to clearly say what your child's problem is. Dermatological lesions need to be seen. Anything else is speculation. See your pediatrician for proper diagnosis and treatment.