But good news came from South Gloucestershire last month. Apart from needing to pass a regular medical, she can carry on as usual - stopping traffic, supervising children and being an almost full-time volunteer at the Meadows.
Her day starts at 8.30am on a main road running into Bristol. "I've only had one car go through me, and the police managed to trace the number and the driver got fined," says Mrs Lock. When the children are all in - "I can more or less tell if there's one missing" - she doesn't think of going home.
On Monday when I rang she was helping in the school office organising disco tickets. She is, after all, a keen member of the PTA. Then there's dinner duty followed by the afternoon session teaching sewing to infants. When the bell goes she's back on lollipop duty and home by five - that's after a stint helping out in the after-school clubs.
"I thoroughly enjoy everything about the school," says Mrs Lock, whose own son and grandson have been pupils there. "It's a very friendly, happy school and the children respond very well. I like it when they call out, 'Hello, Mrs Lock'."
In January, when new head Avis Ball arrived, it didn't take her long to realise the value of Mrs Lock. "I've never met someone who's devoted so much of their life to a school," she says in her nomination for bouquet of the week. "She's so thrilled she doesn't have to retire and said that was the best birthday present in the world."
Thank you and congratulations to Mrs Lock, and I hope she enjoys her birthday celebrations tonight - at the school disco, naturally.
The TES book awards are announced this week, celebrating the brightest and best in non-fiction publishing for children. The awards are in their 25th year and our judges were more impressed than ever by the high standards being reached by publishers in production and brilliant colour photography.
More than 200 entries came into our offices, and now that book buying is suddenly on the agenda in every school, our judges' reports on pages 10 to 13 are well worth poring over.
Bouquet of the Week Names, please, on a postcard - and why - to Sarah Bayliss, The TES, Admiral House, 66-68 East Smithfield, London E1 9XY
Bouquet of the week is given in association with Marks amp; Spencer