Suggestions?

OK, all you readers, regular or occasional lookie-loos, I need your help. Pretty soon we will start really diving in to our third bedroom to transform it into an actual bedroom for the coming kiddo. We’ve done zero decorating in this room, but loved having a separate room for the computer in our little house. But times change!
Here’s my problem. The previoius owners left us these lovely bolts in the wall. I think they would be called bolts? They are like one long piece of metal, including the flat circular part you see on the outside of the wall and a cylinder part that goes into the wall. They are about 3/4 inch diameter (on the flat wall part). There are 5 of them on a prominent wall. My mom is the Family Handyman, and I know she’ll help me, but I wanted to see if anyone has ever had to remove something like this before? The only thing I’ve tried is prying up the sides of the part on the outside of the wall with a screwdriver, but it does not seem very pliable.
Any ideas?