This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Employment Income Manual

Tax treatment of teachers, lecturers and tutors: Association of University and College Lecturers: notes on expenses deductions: equipment

“3. Equipment (for example, tape recorders, record players, slide rules, calculators, drawing instruments, computers and other appliances) 

In general, these items are supplied by the employer where necessary, and the teacher is not necessarily obliged to supply his/her own although he/she may do so from personal choice. No deduction, therefore, can be made for the cost of upkeep of such instruments etc. Exceptionally, where it is deemed necessary for a teacher to provide his/her own instruments etc for use in the performance of his/her duties there may be an entitlement to an allowance.”