The actress first gave $10,000 (£6,271) earlier in the week to the Segue Institute for Learning, which Davis mentioned while accepting a SAG Award in January.
Streep has now given another $10,000 to establish a scholarship fund in Davis's honour in Rhode Island.
Mariam Boyajian - director of Rhode Island's Upward Bound scholarship fund - told The AP that Streep's donation was the largest single financial gift ever received by the organisation.
The Iron Lady star triumphed over Davis in the 'Best Actress' Oscar race last weekend, even after Streep had tipped the Help star to take home the prize in the days before the Academy Awards.
Streep later joked that "half of America" was likely upset to see her win her third Oscar, this time for her portrayal of Margaret Thatcher in The Iron Lady.
> Meryl Streep, Julia Roberts confirmed for August: Osage County
Watch Meryl Streep after her third Academy Award win below: