Teachers have said social distancing was "impossible" to enforce among younger year groups – especially outside the classroom – as schools opened to more pupils on 1 June.
Sharing their experiences of managing pupils in "bubbles", staff reported that it was a "monstrous task" repeatedly telling the youngest children to keep their distance.
Asked on Twitter if social distancing measures worked effectively with their "bubble" on 1 June, nearly two thirds of teachers answered "no".
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A "bubble" is the "small, consistent group" that Department for Education (DfE) guidance suggests staff and pupils stay in throughout the day, away from anyone else, so as to reduce the risk of spreading the virus.
More than 4,400 people responded to the poll, set up by Chris Parkhouse – headteacher at Grove Road Primary in Harrogate – of which 65.6 per cent said the measures were not effective.
Teachers - Did social distancing measures work effectively with your bubble today?— Chris Parkhouse (@chrisparkhouse) June 1, 2020
Some teachers reported that distancing was easier in the classroom, as desks were spaced far apart and children stayed in their seats.
However they said measures were "impossible" to enforce as pupils moved around the school and played outside.
In the classroom it was fine as the desks were spaced apart. Outside - no chance, and not through lack of trying. This was y1.— MrsKS1Teacher (@MrsKS1teacher) June 1, 2020
In response to the Twitter poll, one teacher said: "Yes and no. In older year groups yes. Lower down and key worker group it was a monstrous task repeating the same phrase all day."
Another said: "Mostly okay inside when sat working at desks. Pupils weren’t great outside – they had instructional videos, equipment they could use for solo play, reminder talks and there were only 8 of them but I had to say, 'keep your distance' about 10 times in a 30 minute free play session."
Even the logistics inside the classroom were tricky at times when moving from desk to sink to hand wash. Can all line up socially distanced cannot have some at desks and some lined up and socially distance as room is not big enough. Chn had a ball each at playtime but couldn’t SD— Charlotte Neale (@CNeale78) June 1, 2020
Secondary school teacher Tracy Dorrington, who was looking after children of key workers, added: "I think a better question would be does it work in class, does it work out of class and a yes or no.
"As my students can get it in class (I’m secondary not many students as only key worker and vulnerable) but out of class majority can not do it at all."
No, classroom was managable because they stayed in their seats (not ideal or helpful) but impossible going up and down stairs and in the playground. Impossible for staff because as soon as your space desks in classrooms there is no room to move around safely!— TaraTeacher (@TaraTeacher1) June 1, 2020
Other teachers said there was "no chance" social distancing measures could be enforced among the youngest children.
Chris, a Year 2 teacher, said: "Hahahahahhhaha. My new class are great but NOPE. 4 year old things."
And Rachel Lucey said: "4 and 5 year olds... NO CHANCE!"
But some teachers reported that children were "responsive and honest" and "tried their best".
Responding to the poll, one teacher said: "Absolutely. The Y6s were very responsible and mature."
Thomas Sweeney, who teachers children in Years 3 and 4, said: "Very difficult question to answer... but I went with yes. In the majority the children were very responsive and honest about it. They all understood and followed as closely as children can."
And Rachel Potter said: "Yes, I’m a TA in a year 6 class and must say the social distancing really did work both inside and out."
Separately, Chris Dyson, head of Parklands Primary, Leeds, asked his Twitter followers how many Reception, Year 1 and Year 6 pupils, excluding children of key workers, attended their school on 1 June.
More than 4,000 people responded, of which 52 per cent said no children from those year groups had returned to school.
One in five (20 per cent) said they had fewer than 20 children in school; 17 per cent had fewer than 60; and 11 per cent had more than 60.
Headteacher Anne Wentworth said it had been "quite a tough day", as lots of parents had complained about staggered start and finish times and having children in different socially distanced "bubbles".
Catherine Jollands added: "We are the same, in our Infant School we had about 15 key worker children up until today, now we have 63 key worker children from Nursery to Year2. We aren't able to take any more children."
And Emma Hooper said: "Our [Reception] is starting to come back from 8th. Once they are in and with keyworkers we are full up – no more rooms, no more staff! Didn’t really think about infant schools did they?"
But some teachers reported a more positive experience.
Alexander Jibb said: "First day back very enjoyable with my yr 1 "bubble". Very impressed with organisation by our SLT. I feel much more confident."
And Rebecca White added: "112 from nursery to Y6! Excluding key workers we had 82 children. Staff were incredible, parents were amazing and the children were so happy to be back! #schoolsreopening #weneverclosed".
A DfE spokesperson said: "From this week, many schools have begun welcoming children from Reception, Year 1 and Year 6 back to the classroom as part of a phased and cautious approach.
"To prepare for this, headteachers and school staff have been doing an excellent job including putting protective measures in place and engaging with parents and children.
"We will continue to support schools who haven't yet been able to open more widely to do so as soon as possible."