People concerned about the tests, which were reported by The Canadian Press last week, are expected to gather in seven cities to pray, talk and pressure Ottawa to provide all its information on residential schools to the Truth and Reconciliation Commission.
"People from different backgrounds, they've been telling me they're disgusted," said Wab Kinew, one of the organizers.
"We wanted to provide an outlet for people who are feeling that way to come together, to do something that's spiritual and commemorative, and provide an emotional outlet for people so they're not left feeling negative.
"The more political side is to have the people who gather call on the federal government to hand over the remaining documents to (the Truth and Reconciliation Commission) now, rather than a year after the (commission's) mandate expires."
The commission's work has been hampered by haggling over how far Aboriginal Affairs needs to go in digging up archived documents.
Many Canadians were appalled last week upon learning that the federal government had commissioned research on aboriginals in remote communities in northern Manitoba and at six residential schools across the country during the 1940s.
The researchers knew the people they were studying were hungry, but instead of advocating they be better fed, they chose to use them as unwitting subjects to test the effects of different vitamins and minerals.
The news shocked aboriginals, who thought they knew everything about the abuses inflicted on their people.
"Things that happened to us and were hidden from us are coming out, finally," said Chris Frenchman, 56, while speaking at a Truth and Reconciliation Commission hearing in Hobbema, Alta., on Wednesday.
"We weren't aware of what they were giving us and here a professor confessed that we were being used as guinea pigs, the food that was given to us."
Laurelle White, who also spoke at the hearing, wondered if something similar happened to her.
"With hearing about the experiments that they were doing on children, I thought, 'Wow. That's just not right. How could they do that?'
"And as the day progressed, after I heard about this, I realized, 'Hey. Wait a minute. We were given vitamins.' I still can taste that vitamin."
The experiments were emblematic of how aboriginal people were treated, she said.
"This treatment isn't just at the residential school level. It was just the attitude towards us."
And it's a good example of why the commission needs to see everything, said Kinew. It's a chance for Prime Minister Stephen Harper's government to show it was sincere in its 2008 apology for the wrongs committed in residential schools.
"There is an apology. The jury is still out on whether it's a meaningful one."
As far as the commission's request for documents, the government has said it only needs to hand over papers that have already been tabled in court for survivors' lawsuits over the years. The commission wants a far broader range, a demand recently backed by guidance from the Ontario Superior Court.
Library and Archives Canada estimates it would take $40 million and 10 years to find and digitize all the required records. The auditors say the documentation would need to be pulled from 80 different archives involving 135 schools and would fill about 69,000 boxes.
Aboriginal Affairs Minister Bernard Valcourt has said the government is looking for a way to hand it all over. The commission's mandate ends next July and its supporters want everything to be released before then.
Petitions supporting release of the documents are to be on hand at the rallies. Depending on the location, representatives from the Presbyterian, United, Catholic, Muslim and other multi-denominational churches are also expected to attend.
Rallies are to be held in Winnipeg, Vancouver, Ottawa, Saskatoon, Edmonton, Thunder Bay and Sudbury, Ont.
"Canada is still in this era of coming to terms with what the residential school experience meant," said Kinew.
"We can still get this right by having Canadians from different walks of life standing up and saying this is important to them. And we can still get this right by having our partners in the federal government stand and do the right thing."
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