The public are welcome to go to the school to watch the match, which will be played on Friday May 24 from 3.30pm on the head pitch.
Sir Ian will not be playing, but will also take part in a question and answer session earlier in the day.
Other celebrities and former sports stars taking part include national cricket selector Ed Smith, fellow ex-Tonbridge School student and TV presenter Chris Hollins, and former players Rob Key, Gladstone Small and Paul Parker, along with current Kent and England cricketer Tammy Beaumont.
Tom Chaplin is also an alumnus of the school, and his father, David Chaplin, OBE, is Chief Executive of Rwanda Aid, which is trying to raise more than £20,000 at the event.
David Chaplin said: “The funds will be helping to support young people living with disability in their homes, in school, in the workplace and in the community.”
“As with all our initiatives, we aim for this to be so successful that it will become the model for providing care throughout the country.
“We are enormously grateful to Tonbridge School for making its wonderful cricket ground available to us, and we are looking forward to a fun and entertaining day.”
OLD BOY: Keane’s Tom Chaplin went to Tonbridge School
The event coincides with the 25th anniversary of the genocide in the African country.
Rwanda Aid works in the western province, one of its poorest regions, supporting effective education and opportunity for enterprise; helping the disadvantaged and disabled is central to its work.
There will be a Q&A session with Sir Ian Botham and former Kent captain Rob Key, and a charity auction with prizes including a round of golf with Sir Ian and Tom and a flight in a Tiger Moth plane.
