There is just no way to fill the gap as an RP is a must for admission to schools. Suggest, you allow the children to continue with their education in their home country and bring them here when you get permanent residency for your wife and some months before schools start, However, if your child is in the nursery stage, you may try your luck with some nurseries here in Doha. From what I learnt from the comments of QLers, these nurseries do allow admissions in such cases. I am not sure though.