Why hide the message in 'techo-art', just write the message in cursive and most kids would be stumped. Even Old English or Wedding Text from the lead type setting days printed in all caps could cause a "solve it" quiz today.
As one who has taught cryptography in the past, this is just lame. I suppose they have to make it easy so people can feel good about themselves and their purchase... Are they desperate for sales or running out or crap for stamp subjects? As was mentioned before, this is just a terrible font. I like the cursive suggestion.