Their report suggests many emergency visits are unnecessary as children's illnesses are often minor. And this can lead to "undue distress" for families.
But patient charities say parents often turn to A&E if they cannot get GP care.
Experts say there is an urgent need for more GPs and better GP training in child health.
Children make up more than a quarter of accident-and-emergency attendances in the UK.
But experts at the Royal College of Paediatrics and Child Health (RCPCH), Royal College of Nursing and the Royal College General Practice (RCGP) have joined forces to suggest hospitals are not always the best places to be seen.
Dr Hilary Cass, president of RCPCH, said: "The vast majority of children's illnesses are minor and require little or no medical intervention.
"So a significant number of these attendances at the emergency department are unnecessary - and putting extra pressure on the system and causing undue distress and disruption for families.
"But of course every attendance means that a parent is worried about their child's health, and either unable or unsure about how to access a more appropriate service."
Their new guidelines says children who are mild to moderately unwell could often be cared for better in communities, closer to home.
The report makes several recommendations to improve GP and other community care, including:
But Katherine Murphy, chief executive of the charity the Patient's Association, said there also needed to be better access to GPs.
She said: "It can be frightening for children to end up in A&E. They might be better cared for in the community in many cases.
"But very often parents take their children to A&E because they can't get access to their GPs.
"They know they won't be turned away from A&E and won't need to wait days for an appointment.
"We need better access. And there needs to be more awareness raised of services such as minor injury units."
Prof Nigel Mathers, of the RCGP, said it was crucial that parents with a sick child could see a GP when they needed to.
"But unfortunately what we are seeing is a severe shortage of GPs, and this is having a serious impact on the waiting times for a GP appointment," he said.
"The RCGP is calling for 8,000 more GPs in England."
Worried parents are putting "extra pressure" on A&E departments because they are unsure how to get more appropriate care, leading doctors warn.