What timing arithmetic is actually for

1What the clock is showing

An answer in a second has been remembered. An answer in twelve has been rebuilt - counted on fingers, or assembled by making ten. Both arrive. They do not both carry forward.

In 27 + 15, the ones column has to be worked out while the tens are held in mind. A child who spends twelve seconds on the ones has nothing left over to hold the tens with. Speed here is not the goal in itself - it is the room the next step needs.

2Four seconds and ten

This drill splits a first-attempt correct answer three ways: under four seconds, under ten, and longer. Each gets a different mark.

Four seconds sits around the boundary between recalled and reconstructed; ten is where it is safe to say the fact is not yet automatic. A bar on screen shows where the current answer stands while it is being worked out - the threshold is not hidden. Better a line you can see moving than a verdict delivered afterwards.

Neither number comes from a study. They were set by solving on this screen, with its keypad, where how fast a finger moves is part of the total. They are not an absolute standard so much as a line for watching one child change against.

3The case against the clock

Timed arithmetic tests have long been blamed for making children afraid of maths. Under time pressure, facts that are known stop arriving. And a belief about oneself - "I am bad at maths" - can set long before the ability it claims to describe.

The criticism lands. The moment speed becomes the point, practice becomes a contest - and a contest works for the children who are winning it while quietly excusing the ones who most need the practice.

4Where the clock is switched off

So the timing is narrowed instead.

• There is no time limit. Nothing is cut off, and slowness never turns a correct answer into a wrong one. However long it takes, right is right
• Speed only separates first-attempt answers. A correct answer after a miss gets the same mark however fast it came. What is being acknowledged there is the correction, and speed has no business in it
• Times stay inside the child's own record. No leaderboards, no ranking. The only comparison available is with last week

The reading here is that measuring is not the problem - what the measurement is then used for is. Feeding it into which topics come up more often is one thing; pressing the child with it in the moment is another.

5Speed is a symptom, not a target

There is no such thing as practice at answering faster. Speed falls out of knowing the fact. So when a slow topic shows up, the response is not "be quicker" - it is to ask for that topic a little more often.

That is the whole reason mean time is one of the ingredients in the weakness score - and why it is weighted below accuracy, since being wrong comes first. The rest of that calculation is in how weakness is measured.