Fortunately, the lesson I'm about to describe was not mine. It describes how a lot of time was wasted. Even more annoyingly, it was entirely avoidable.

I was observing the first lesson of the new Year 7 (11 year olds) in the computer lab. The teacher, a deputy head, was giving them their network log-in details.

This consisted of calling out their names in turn, telling them what their details were, and then getting them to try it out. Each one took around 2 minutes, and there were 30 kids in the class.

This activity took up the whole lesson, which was bad enough. What made it even worse was the fact that until or after a child had been given their log-ins, they had nothing to do. So out of a 60 minute lesson, each pupil was idle for 58 minutes.

Obviously, it wasn't quite that bad: time has to be allowed for entering the room, a short intro by the teacher, and then packing up and leaving. So, erring on the generous side, I'd say the pupils weren't doing nothing for 58 minutes, but perhaps 45 minutes.

Imagine going to a private tutor for some Spanish lessons in advance of your planned vacation in the summer. You site there doing nothing for 45 minutes, and then at the end of the hour the tutor says, "That will be £25 please?". What would be your likely response?

The whole activity could have been reduced to almost no time at all. One way would have been to have given each pupil a sticky label for them to put into their homework diary. The label would consist of their username and password. Five minutes to give them out, then 5 minutes for the pupils to try logging in. Job done.

Even better, parents of the new intake should have been sent a letter, (or an email these days) saying what their child's details were and stipulating that the child must bring those details along to their IT lesson, in just the same way that pupils are told what the PE kit comprises and that they must bring it along on the days they have PE. Time taken to give out the details in the lesson: zero.

Logging in should be a non-problem. As well as the strategies suggested above, others include the following:

• Keeping details of the pupils log-ins yourself, for for when a pupil forgets their details.
• Keeping a list of spare user identities and passwords.
• Label each computer, laptop and tablet with a label stating what the guest log-in details are for that device, a log-in that will give the person access to all the standard programs.

We've recently changed our doctor's surgery. A week later, for the first time ever, we each received a small card stating our name, NHS number, date of birth, name of the doctor, and the doctor's phone number. It will come in pretty handy not just for us, but for anyone who comes across one of us after we've been run over by a bus (or, more likely, by a cyclist who hasn't worked out that the pavements are supposed to be for pedestrians; I can feel my blood pressure going up, so I'll drop that particular subject now).

Cards like this, containing all the details someone needs in order to access a service easily and quickly, take very little time and money.

They just take a bit of thought, and a bit of planning.