The Weird-Ohs characters werew created by artist Bill Campbell, and made their first appearance in model kits released by Hawk Models. They are in the same sort of genre as Odd Rods or the Nutty Mads, basically gruesome but humorous monsters that appeal to children (with the different that they don't necessarily tie in with the custom car craze).
The card fronts depict color artwork featuring one of the Weird-Ohs characters, surrounded by a white border with the character's name and the card caption below. The card backs feature a very light lime green color against a white background; to the left on every card back is the character of Francis the Foul dribbling a basketball; above and to the left of his (her? its?) head is the card number. In the area to the rigth is the set title, followed by the character's name and a block of text. The copyright indicia is at the bottom.
These cards, although certainly vintage and displaying a popular subject matter (i.e., monsters) are nevertheless reasonably priced and not difficult to find.