Alternatives to educational suppliers. I buy the equivalent from amazon etc at a fraction of the cost. Same with coffee, handwash, cleaning etc.
Amazon also have a scheme if you are a registered charity that gives you up to 10 percent cash back for purchases. Think at the moment it's only on books, however anyone can click the link.
do an inventory of all the software the school uses. I did this a few years ago and without mentioning why I then created an internal survey using google (free) to find out who used what. We saved quite a bit there.
Email newsletters and anything else. Let parents know limited printed copies available from office. Also utilize notice boards.
Centralize stationary, paint etc and have one person responsible for re-ordering. Each class is fully equipped at start of every year.
Shop around for printer deals.
Is it beneficial to train staff in certain areas rather than buying in? Remember they can also be hired out to other schools.
Lloyds bank work with a lot of schools and send in volunteers- have seen them being used as additional lunchtime support, reading interventions etc. they stay for about a hour. They also work with schools to come up with ideas to raise cash.
Look at previous school trips and is it possible that they could have been walked to or used public transport? A lot of schools here rarely use coaches.
Do look at hiring the school out. But look carefully as this can cost the school more. One school rents out various parts of the school to different groups at the same time - swimming pool for groups after school when local pool is busier - pitch for 5 a side - hall for dance. If near a football ground or other sports venue rent out the car park.
Cleaner if agency consider other options. A couple of schools hire individuals from external/internal - couple of ta's do overtime same with midday people.
If using Apple devices are you utilizing the bundle discounts?