Children are unlikely to be allowed to bring pencil cases to school when they reopen - but lunch boxes will be fine.
England's deputy chief medical officer Dr Jenny Harries said scientists are looking at what youngsters will be allowed to bring into school to minimise the risk of Covid-19 being passed on.
Education Secretary Gavin Williamson today defended plans to partially reopen primary schools from June 1 - admitting teachers and parents are "anxious" about the move.
Under new guidance, children will not be allowed to bring in their own pencil cases.
Schools will also have to increase measures to make sure surfaces and items which children and adults touch are clean.
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Dr Harries told the Downing Street daily briefing: "The basic public health principle is you want to keep everything as clean as possible - touch points if you like, so the things we normally think of as door handles and those sorts of things, wipe down and clean frequently.
"I think the thing in a children's environment is there are certain things that you can control pretty well, which might include pencil cases and things that you use routinely during education, and by doing that, schools can provide them and ensure that they are maintained clean.
"The issue about lunch boxes is they're quite personal to the child eating the lunch, and I can almost guarantee that one child won't want to eat the lunch of the one sitting hopefully two metres distance from them."
Responding to a question from the Sunday Mirror's Nigel Nelson, she continued: "And actually when you're eating you're also putting your hands up to your mouth and to your face so there is a differential there around risk both on what individuals need and what the school can supply and on managing the hygiene around it."
She added hygiene was important for both lunchboxes and pencil cases, and stressed the need to encourage children to wash their hands before and after eating.
The Government expects children to be able to return to nurseries and childcare settings, and for reception, year one and year six pupils to be back in school, from June 1 at the earliest.
She said: "Although it is recognised that small children will run around and interact, we expect them to, but you can still distance. I know this is the plan."
She also suggested that desks could be placed appropriate distances apart from one another to prevent long periods of close contact.
Dr Harries added: "A child rushing past another one in a normal area is probably not much of a risk.
"But if they were sitting directly opposite to each other in a very small space, close together for a long amount of time - that might be more of a risk.
"All of the interventions are designed to minimise those, while still allowing children to learn."
From next month, Mr Williamson said, children will qualify for coronavirus testing if they show symptoms.
A track-and-trace system will be introduced to prevent the killer bug spreading as a result of schools reopening, he told the daily Downing Street briefing this afternoon.
Mr Williamson said: "The longer schools are closed the more children miss out. Teachers know this."
And he added that for some, school is the "safest place to be".
