Eric Morecambe (of Morecambe and Wise) wrote a couple of very funny children's books about a vegetarian vampire. Now his son Gary has taken up the mantle with Count Krinkel-fiend's Quest, the first in a series called "The Tall Tales of Dracula's Daggers" (Scholastic pound;4.99). Vampire expert Professor Erich von Morcumstein investigates reports of a cloaked figure turning into a bat somewhere in the kingdom of Gertcha. Nines and over will love the humour in wordplay and plot.
The Secrets of Vesuvius in the immensely readable Roman Mysteries series by Caroline Lawrence (Dolphin, 4.99), again features a kind of classical Famous Five: Flavia Gemina and her friends, Jonathan, Nubia and Lupus, plus Scuto the dog, meet the great Pliny while on holiday in Pompeii and end up near Mount Vesuvius on the fateful night it erupted.
An enormous amount of information about the ancient world is conveyed under the guise of a jolly good romp.