Police were called to Clapham Terrace Community Primary School on Tuesday
Police were called to a school after it was reported two boys had poured a "bleach-like substance" into their teacher's coffee.
A female teacher was targeted at Clapham Terrace Community Primary School in Leamington Spa, according to The Sun.
Warwickshire Police confirmed officers had been sent to the school on Tuesday.
It added the boys "did not realise the seriousness or severity" of what they had done.
Police said it had been an "isolated incident", which was dealt with internally by the school.
It came a day after schoolteacher Ann Maguire was stabbed to death at a school in Leeds.