Calls are being made for a "symbolic change" to the description of religious assemblies in some schools.
The Church of Scotland and the Scottish Humanist Society have told MSPs the title "religious observance" in non-denominational schools is outdated.
They said changing the legal definition to "time for reflection" could ease the concerns of parents who withdraw their children from such events.
They claimed this would give more pupils the chance to explore faiths.
The groups have made their call in a submission to MSPs on Holyrood's petitions committee.
The law requires religious observance, such as assemblies, in schools.
However, since a change in government guidelines in 2005, assemblies should be aimed at children of all faiths and none.
The Church of Scotland and the Scottish Humanist Society argued that this now often means assemblies would be more accurately called a "time for reflection".
Their joint submission to the petitions committee states: "The change to a more equal and inclusive 'time for reflection' would echo the current practice of the Scottish Parliament, and bring legislation into line with modern views.
"It will also remove the current focus on 'religion', with which many non-religious people struggle."
The Free Church of Scotland said the proposal was a "disaster" for both Christians and children.
The Scottish government believes the current legislation and guidance is appropriate.