Owls are not in children's everyday experience so it is not a topic which will be rich in possibilities for attempts to explain or questions to pose or theories to represent. A topic like the grocery store is likely to much more productive. The children have experience, they are fascinated by what they see going on there, adults do important things there, they use various tools and equipment, they have different jobs, etc. etc. The topic is rich in possibilities. One of the key characteristics of a topic rich in possibilities for project work is that it is something you can investigate first hand through field work, observing real objects or processes or talking to experts.
Questions arise as young children represent what they have experienced and know about.
As they try to include details in their representations they realise they need to find out more than they already know. Then investigation becomes necessary to them. It would be very helpful to other teachers if you would tell short stories or vignettes about things which are happening in the context of your projects. I look forward to hearing more from you soon.