I have a character who is a sorcerer with the Elemental(Air) bloodline. She's now 9th level and can thus cast Elemental Body (it's a bonus spell at that level). It hasn't come up, yet, but I foresee her wanting to cast other spells while this spell is still in effect. My initial take was to not allow her, but I'm rethinking that a bit. If she's amorphous, then she should be able to handle somatic components, at least theoretically. If she can make sound she should be able to handle verbal components, maybe. Sorcerers already have Eschew Materials as a feat at 1st level, so most material components should be taken care of. Am I missing something, or should other spellcasting work while in this form?
Elemental body places no restriction on spellcasting
Nowhere in the elemental body spell is any limitation on spellcasting offered. It simply says you take the forms of the various elementals.
Elementals are capable of casting spells
Unlike animals, elementals can talk, tend to be roughly humanoid in appearance, and thus can perform gestures and manipulate materials and foci. Elementals can take levels in spellcasting classes, and when you become one you remain capable of doing everything that’s necessary for spellcasting.
So yes, you can cast spells during elemental body.
All your items meld during a polymorph effect
This would include your spell components, which is problematic for spellcasting. A sorcerer, of course, has Eschew Materials, and anyone else could take it, so that would be one solution for negligible-cost components, or you could just keep the components separate while polymorphing.
Considering how easy it is to get around, and how it really seems like it’s supposed to be a convenience feature for the transmogrifier, I probably wouldn’t bother enforcing this rule though. I could see abuses that might make me put my foot down, but for the most part it’s probably fine.
Polymorph subschool places restrictions on spellcasting.
It will depend on the spell components needed for each spell.
You will need natural spell or eschew material if the spell has somatic components.
Elemental body is a polymorph subschool spell.
According to the SRD :
When you cast a polymorph spell that changes you into a creature of the animal, dragon, elemental, magical beast, plant, or vermin type, all of your gear melds into your body. Items that provide constant bonuses and do not need to be activated continue to function while melded in this way (with the exception of armor and shield bonuses, which cease to function). Items that require activation cannot be used while you maintain that form. While in such a form, you cannot cast any spells that require material components (unless you have the Eschew Materials or Natural Spell feat), and can only cast spells with somatic or verbal components if the form you choose has the capability to make such movements or speak, such as a dragon. Other polymorph spells might be subject to this restriction as well, if they change you into a form that is unlike your original form (subject to GM discretion). If your new form does not cause your equipment to meld into your form, the equipment resizes to match your new size.