The confectionery firm has asked a number of digital agencies to submit ideas for the online activity, which will include improved services on the portal.
The company is also redeveloping the Cadbury Learning Zone, its curriculum-based online learning platform for children, parents and teachers.
In the light of the ongoing debate about obesity and marketing confectionery to children, Cadbury has emphasised to agencies that development ideas for building the learning tools on the web site must not involve offering its chocolate products as prizes or rewards for performance.
Cadbury Trebor Bassett new media manager Frances Dovey said it was approaching agencies "to see what is on offer and potentially to add to our roster".
She added that the search would not necessarily result in a change to the current roster, which was created a year ago and includes E3 Media, big:group, EHS Brann and nowwashyourhands.