3 half or 5 half days?!

*sigh* Registration for Pre-4 preschool started today. Marcin and I discussed and we decided to sign Gavin up for 5 half days. There is also the option for 3 half days. He has been doing 2 half days this year for 3 y/o preschool. Initially the school only offered 3 half or 3 full days, so we were set on 3 half days. But then the school acquired another school so they are offering a couple different more options, like 5 half days. When I first saw this....I immediately thought, 5 half days would be good.
Marcin is fine with the 5 half days. I keep going back and forth between the 3 half days and the 5 half days.

We decided on 5 half days because:

1) We felt it might make full day kindergarten transition a bit easier for both Gavin AND me :-P

2) He is July baby so he is on the younger side. We are open to the fact that he may not be ready for Kindergarten at 5 y/o. So we also thought going 5 days at 4 may help him learn the skills he would need to Kindergarten....mainly the sitting still and focusing parts :-P

3) I will have two 2 y/o's at home.

I want 3 days because:

1) I will miss him, plain and simple.

I can still change my mind........I feel like the 5 half days is the right thing but then I am sad :-(