We consider a model with three economic agents: a certifier, a sender and a receiver (e.g., test provider, student and school). The sender has imperfect private information about the state of the world (e.g., student's ability), assumed to be binary. The certifier offers a menu of tests with different prices, from which the sender chooses her preferred option. The test generates a certificate which is informative about the state and therefore guides the receiver's action (e.g., admission decision), also assumed to be binary. The sender would like the receiver to always take the high action, but the receiver would only like to do so if the state is high. The test may provide information to the receiver through two channels. The first channel is informativeness of actual tests. Second, selection of different types into different tests conveys information, as the receiver updates her belief about the state based on which test the sender chooses.