If you are a first-time IV client, the first day will take about 2 1/2 hours, and the second/third day less than 2. If you do not mind people seeing you like it, you can go into work after, with a load of bandage on your wrist covering the cannula (which can stay in place. There should be no technical reason why you should not get a morning or an afternoon doing your normal thing.
If you can arrange it at short notice, arrange to work in the morning, and have the IV in the afternoon - then you can go home and rest. That means only two days of having a big bandage on your wrist,
I did it, but had the IV in the morning, and then went on to the Uni. It’s great, you can get people to help lift, carry, move, etc. Mind you, I have not taught school children, so I have no idea what other problems you could face.