In 1984, the Portside Festival Marketplace shopping mall opened along the Maumee River, on the site of the former Tiedtke's department store.
There were hopes that the mall might revitalize downtown Toledo, but it closed in 1990.
A mayoral committee appointed to find the best use for the site heard repeated community requests for an educational family attraction.
The city asked COSI Columbus about its experience and resources, and subsequently the city and the Columbus organization created COSI Toledo, an independent, not-for-profit organization with a board of trustees from northwest Ohio.

A fundraising campaign raised $9.5 million, surpassing the goal by $4.5 million.
The state government gave another $10 million.
The former Portside Festival Marketplace facility was transferred to COSI at a value of $16 million.
On March 1, 1997, COSI opened its doors to the public.
The facility attracted an average of 250,000 visitors per year over its first decade.

In 2005, COSI won a National Award for Museum and Library Service from the Institute of Museum and Library Services, the nation’s highest honor for extraordinary public service by a museum or library.
The award was presented by Laura Bush at a White House ceremony in January 2006.

On July 28, 2006, COSI Toledo and COSI Columbus legally split so each could focus on their own financial troubles.
Later that year, Berrien Springs Public Schools awarded a 2006 Teachers' Choice Awards to COSI for its distance learning program.
After voters voted down a second levy in November 2007, COSI Toledo closed due to lack of funding on December 31, 2007.

On November 4, 2008, Lucas County, Ohio, voters approved an operating levy for the science center, enabling it to reopen in fall 2009.
In 1984, the Portside Festival Marketplace shopping mall opened along the Maumee River, on the site of the former Tiedtke's department store. There were hopes that the mall might revitalize downtown Toledo, but it closed in 1990. A mayoral committee appointed to find the best use for the site heard repeated community requests for an educational family attraction. The city asked COSI Columbus about its experience and resources, and subsequently the city and the Columbus organization created COSI Toledo, an independent, not-for-profit organization with a board of trustees from northwest Ohio.
A fundraising campaign raised $9.5 million, surpassing the goal by $4.5 million. The state government gave another $10 million. The former Portside Festival Marketplace facility was transferred to COSI at a value of $16 million. On March 1, 1997, COSI opened its doors to the public. The facility attracted an average of 250,000 visitors per year over its first decade.
In 2005, COSI won a National Award for Museum and Library Service from the Institute of Museum and Library Services, the nation’s highest honor for extraordinary public service by a museum or library. The award was presented by Laura Bush at a White House ceremony in January 2006.
On July 28, 2006, COSI Toledo and COSI Columbus legally split so each could focus on their own financial troubles. Later that year, Berrien Springs Public Schools awarded a 2006 Teachers' Choice Awards to COSI for its distance learning program. After voters voted down a second levy in November 2007, COSI Toledo closed due to lack of funding on December 31, 2007.
On November 4, 2008, Lucas County, Ohio, voters approved an operating levy for the science center, enabling it to reopen in fall 2009.
Imagination Station