Scavenger hunt for telling husband about pregnancy?

I asked my husband to check the oven for me. When he did he found a hamburger bun. Get it? A Bun in the Oven. Ha ha. Of course he is from New York and calls buns rolls and so he screwed it all up by saying there was a roll in the oven instead of a bun. He still thought it was cute. Oh, the scavenger hunt isn't going to work very well if you leave baby hints. He'll know what the surprise is after the first one. You could leave the pregnancy test at the end of whatever you set up. That's always a shocker.