Is telling a girl straight out you like her a bad thing?

it depends. If your not afraid of rejection, then you could tell her straight foreward. Just in case she doesn't feel the same way. Thinking in a different perspective, if this girl doesnt like you, it would put her i an awkward position if you tell her that you like her. What i'd do, is start out as really good friends or find out if she likes you back. Then you could tell her straight foreward that you love her :)