Worried mums have handed in a 1400 signature petition to Tudor Grange Academy, urging the school to rethink plans to alter its admissions policy.
The lion's share of signatures were submitted online and topped up by people stopped in Solihull town centre last month.
Speaking to the Solihull News outside the school gates, parents said that the changes could lead to a seismic shift in policy across Solihull.
Mum Biro Dhillon said that if Tudor Grange pressed ahead with plans to give priority to two CofE primary schools - other academies may follow suit.
"There could be a domino effect across Solihull," she said. "This would see every school moving towards a system where they pick the children they want.
"Parents may have to start thinking about their child's education when they're two or three, because they need to get them into the right primary."
Even though Tudor Grange's plan to give preference to St James' and St Alphege has not been finalised, there has also been a flurry of parents seeking to move their children into the two schools.
Mum-of-two Tina Briggs was one of those who bought her house to secure a place at Tudor Grange and was not reassured by a recent meeting with executive principal, Jennifer Bexon-Smith.
"This school has served the community for decades and it seems unfair that people who live a five minute walk away could be bumped off the list while those who are driven in are offered a place."
Cheryl Shepherd was at the school with her daughter, 17-year-old Tanaya, a former Tudor Grange pupil.
"I have four boys who I would want to come here as well, but now I'm worried they wont get the opportunity," she said.
"It's such a shame this has happened because it is a good school."