My husband works so hard for us at work and at home and I wanted to let him know how much I appreciate him and love him. He and I work much different hours and so it wasn't hard for me to find time while I was at home and he was at work to do something for him. So, one night I headed to Target and got the biggest chalk they had - the guy at the checkout did give me a little bit of a strange look for coming in at 9:30 PM and buying only chalk as a grown adult and heading out, but once I told him my idea and what I was doing he loved it - I wouldn't even be surprised if he does it some day too for someone he cares about; I hope he does!
I headed home, with my newly purchased chalk, and starting coloring. It honestly was really fun - I hadn't used chalk on the sidewalk (or in this case in our garage) since I was a young girl and I had a blast. As you can see I wrote "I LOVE YOU" in the space in our garage that my husband usually parks in.
I was so excited for my husband to come home from work that night and see it. When he did finally come home, he LOVED it. We left it on the garage floor until it wore off naturally.
You can surprise your husband, or kids, with this idea and write anything you want. I hope you have fun with it!