The former headteacher of Hornby High School said she wasn't sure what to do next when the school was shut down in 2009.
On being elected leader of Lancaster City Council last week, the Bulk Ward councillor told the Lancaster Guardian that back then she would have "dismissed the idea out of hand" but is now both "amazed and happy" to be where she is now.
Coun Jackson said the Green Party's leadership bid in Lancaster was for a change of style, rather than a change of policy content.
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She dismissed claims that the Green Party had formed an alliance with the Conservative Party in Lancaster, and that the vote came down simply to how fellow councillors felt on the night.
"We put forward our leadership as a change of style and we spoke in full council to explain that we wanted a co-operative and kind form of relationship with the chamber," she said.
"We went into the leadership contest not knowing if the votes were there, but we wanted to stand for what we believe in, and it came down to what people felt on the night."
Coun Jackson said one of the major challenges in the Lancaster district was the recovery of businesses following the Covid-19 pandemic and the reinstatement of tourism and attractions.
"We want to ensure the centres of both Lancaster and Morecambe can thrive again," she said.
No stranger to community involvement, Coun Jackson is a trustee of Morecambe Bay Foodbank, director of MORE Renewables, an occasional Street Pastor helping young people get home safely, a governor at Castle Hill Primary School, and helps run a food club on the Ridge Estate within her ward.
She also collects food from Preston FareShare for a food charity that she volunteers with each week, and founded the Claver Hill project - buying land to the east of Lancaster a few years ago which she is now in the process of gifting to the community in perpetuity.
The land is used to grow food for local people and hosts a number of community groups including refugees who run a growing project on the land.
Coun Jackson's last job with the council's cabinet was that of Portfolio holder for Housing.
In that role she oversaw the retrofitting of council houses to make them more sustainable, and the development of Street Aid - an innovative digital giving project enabling residents to donate to homeless people via contactless pay terminals in shop windows.
She also ensured that all homeless residents were housed during the pandemic.
"The work we've done around homelessness is something I'm very proud of," she said.
"It has forced us to face the problems, and has involved a lot of patience and hard work from city council officers, as well as the third sector and the NHS.
"It was about tackling the causes of homelessness, rather than moving people from place to place.
"Until the root causes are addressed, we can't begin to deal with it.
"It has been a real transformation for me, and taught me about how we can affect a problem that seemed like it would never go away.
"But now I feel like as a community we've faced it, and made progress and it gives me heart and belief that we can apply this to other problems too."
Coun Jackson said she was delighted to have been elected leader of the council.
"We have an exciting policy agenda and addressing the climate emergency is at the heart of it, alongside ensuring that our residents have safe, warm homes, and that we work as a sustainable, compassionate and responsible council.
"I'm looking forward to working with staff, residents and my fellow councillors to ensure that this wonderful district continues to thrive as we recover from the pandemic."
She noted the Eden Project North in Morecambe, Bailrigg Garden Village in south Lancaster, Canal Quarter, the Citizen's Jury action plan, and the Mainway redevelopment in Skerton as some of her top priorities over the next two years.
"More social housing is also a priority," she said.
"Particularly specialist housing for older people, encouraging more community led housing like the project in Halton, affordable homes, and then the West End of Morecambe all of which we'll be involving the local community in.
"The other main priority is digital skills and 'electech', improving the job opportunities and skills training in this area, as well as looking to further green building, and retrofitting homes.
"I met with the chief executive and assured him that we won't be changing the agenda - we've got a set of corporate priorities that we'll still be working to."
Coun Jackson said that Lancaster residents shouldn't be worried about further cuts as a result of the pandemic.
"Covid has cost us money and has reduced our income," she said.
"But what it has also done is make us prioritise the things that we want to get done."
She also said that the rural areas of the Lancaster district had often been overlooked, and this was something she wanted to address during her tenure, as well as helping and enabling community groups in Morecambe to change the town for the better.
On becoming the first ever Green Party leader of Lancaster City Council, she said: "I think it tells us that we have got a district that represents a wide political agenda, but it's coming together over issues like climate change, and there's a willingness to trust in the Green Party.
"The Greens have been on the council for 22 years, and there's a respect for the fact that we know what the issues are, and that we take the concerns of all of our residents very seriously,
"It's a really big new challenge, but I face it with a lot of support from the Green group, and hopefully by the other political groups too."
She added: "We work best when we are working together for the benefit of our residents.
"That means political inclusion rather than political competition.
"I'm delighted that colleagues from the Eco-Socialist Group, the Morecambe Bay Independents, the Liberal Democrats and Labour, will be working together with the Greens.
"Cabinet will reflect diverse views and in particular will have strong representation for Morecambe so that we can continue to implement the policies and strategic plans put in place over the past two years.
"I am looking forward to working collaboratively to achieve our aims and have appointed councillors from a range of parties who have the right skills and abilities to do their best for this wonderful District."
Coun Jackson replaced Labour Coun Dr Erica Lewis as Leader of the Council after a vote at the Annual Business Council last week.
Four Green Councillors - Couns Gina Dowding, Tim Hamilton Cox, Dave Brookes and Caroline Jackson continue on Cabinet in their roles working on Strategic Planning and Placemaking, Sustainable Economic Prosperity, Environment and the Leadership.
They are joined by Coun Kevin Frea of the Eco-Socialist group who is Deputy Leader with responsibility for the Climate Emergency.
Couns Tricia Heath and Cary Matthews from the Morecambe Bay Independent Group will work on Business and Economic Pandemic Recovery and Housing respectively.
The Labour members and their responsibilities are still to be confirmed.