Hyphenated last names

Jackee
What are your thoughts on it? I'm pretty dead set that I want to hyphenate my sons last name due to I want him to somewhat have the same last name as my daughter. I don't want to double barrel it. The father and I aren't together. He recently decided to finally participate after me contacting him about the gender so since he's finally deciding to be involved and communicate with me I thought I would add his last name as well (at one point I was just going to use my last name due to I didn't think he would want anything to do with it until the day of or day after birth). Anyone's child have any problems with this in school or with at all? I had a little boy in my class who's last name was hyphenated and his parents were married also he knew his full name and spelled it out with no problems.