Character World, Little Star Creations and Redan all appointed by Bulldog Licensing.
Bulldog has added three more licensees to the growing programme for pre-school show Super Why.
Character World will be creating bedding, Little Star Creations will develop colouring and activity books, while Redan will include the title its Fun to Learn range.
The trio join RC2 (master toy) and Cesar (dress-up), while Melbry Events is conducting a series of events in shopping centres across the UK including the characters from the show.
"We are delighted to have signed three more top licensees," said Bulldog's Rob Corney. "It's further evidence of just what a hot property Super Why is. There will be plenty more to come during the rest of 2009 - the RC2 range is set to grow throughout the year and we are also due to announce new licensees for apparel and several other new sectors."