The play zone follows a recent £400,000 splurge on trees and bulbs, a performance area, new signs and railings, better paths and a drinking fountain.
The latter improvements were funded by the mayor of London's Help a London Park scheme, an initiative to pay for work to 10 parks chosen in a public vote.
Friends of Avery Hill Park also unveiled an eco cafe with clay blocks and wool insulation recently to replace one destroyed in an arson attack. Funding for the new cafe came from insurance from the old building as well as from the sale of a nearby local authority-owned property.
Friends group chair Paul McQuillen said "The old cafe was the heart of our park. Its destruction and subsequent call for a replacement led to the formation of our group."
Councillor John Fahy added: "The cafe is more than just a place for a cuppa - it's the meeting point for park users of all ages."