I used a similar type of reading log in my classroom. However, I found that students would start their reflections the same way each day. I decided to add the possible sentence starters on the bottom to get them going when they respond to literature.
I usually assign this on a Monday and collect it the following Monday. For second grade, I start with 50 to 100 minutes a week. They can choose to break apart those minutes how they want during the week, but I assign a minimum number of days that need to be filled out.
I included a few versions - if you wish to add lines to the response section or not.