Dear Ketty Rain,
ASA. Yes, Arabic grammar as a subject, is difficult to learn. And reading and comprehending in context is easy. That is basis of the Doman approach. The children will learn to decipher/figure out the rules of grammar/patterns by reading and comprehending in context. They do not need to know WHY the grammar rules exist at this age. Just to read and comprehend is all. The Middle Eastern methods of teaching Arabic are difficult at best!
Please read another thread here to understand the process of learning a language:
http://forum.brillkids.com/aal%27rby/stages-of-learning-arabic-(or-any-language)/The Doman method begins with words and then couplets (2 words), phrases (3 words), sentences (4, 5, 6+ words) and books (5 sentences). It is an incremental process. I am using Qur'an to teach my children by pulling the words from Juz Amma and will create the additional steps. For Modern Standard Arabic, it is easier when you use tashkeel (and make sure it is correct because that is the basis of the grammar rules that will be explained later) and that your couplets/phrases/sentences are all grammatically correct.
Another site with great materials/examples that include tashkeel is found here >
http://www.arabicfirst.co.uk/ .
When making your .ppt, include all of the tashkeel/grammatically correct materials for MSA. Then you set your child up for success in understanding grammar rules later, insha'Allah.
Please ask any questions and I will do my best to help, insha'Allah.
ASA
Ayesha