Foundation Stage Profile assessments were first collected for the whole cohort in England in 2006/07. This means that those completing Key Stage 4 in 2017/18 were the first for which we can link assessments at Foundation Stage and Key Stages 1, 2 and 4.

What is the relationship between assessments at different Key Stages?

And how do they vary for different groups of pupils?

### The relationship between assessments at different Key Stages

Of the 511,000 pupils in maintained secondary schools who completed KS4 in 2017/18, 453,000 (89%) can be matched to attainment data at Foundation Stage and also at Key Stages 1 and 2.

For attainment we’ll use:

• Foundation Stage: Foundation Stage Profile total score
• KS1 and KS2: average National Curriculum Level in reading and mathematics
• KS4: average score in the English and mathematics components of Attainment 8

The table below shows the correlation between prior attainment and outcomes for each combination of Key Stages. The closer figures are to 1, the greater the correlation.

As we would expect, correlation reduces as the length of time between two assessments increases.

### The relationship between Foundation Stage and Key Stage 4 attainment

We’re now going to look in detail at the relationship between Foundation Stage and Key Stage 4 attainment, exploring how things vary by the following pupil characteristics:

• Gender
• Disadvantage: pupils are divided into five groups based on the percentage of time they have been eligible for free school meals during their time in school: 0% (referred to in the rest of this analysis as never FSM), 1-24%, 25-49%, 50-79%, 80% or more (referred to in the rest of this analysis as long-term disadvantaged)
• Impact of disadvantage: pupils are divided into two groups that we have defined in previous work, based on the impact that disadvantage seems to have: a high impact group, mainly consisting of white British pupils, and a low impact group, consisting of pupils of most other ethnicities

Based upon the above groupings, the highest attainment is associated with girls in the never FSM and low impact groups, and the lowest attainment is associated with boys in the long-term disadvantaged and high impact groups.

The chart below shows how attainment at KS4 (average English and maths GCSE grade) varies according to Foundation Stage score for these two sets of pupils, as well as for all pupils.

Apart from a slight narrowing at high levels of attainment, differences are fairly consistent. The lowest attaining group (boys, high impact, long-term disadvantage) attain around one GCSE grade lower than would be expected if they made average progress based on their Foundation Stage score.

A table showing this data for all combinations of characteristics is available here.

### When do gaps emerge?

What happens if we break down the differences in progress for each Key Stage?

This can be done by calculating three value added scores:

• Foundation Stage to KS1 using Foundation Stage score linked to average level in reading and mathematics at KS1;
• KS1 to KS2 using average level in reading and mathematics at both KS1 and KS2;
• KS2 to KS4 using average level in reading and mathematics at KS2 linked to average GCSE grade in English and mathematics at KS4.

For each combination we can calculate a value added score for each pupil, then put them on a common scale (normalise them), to enable us to compare value added scores for each of these Key Stages.

The table below shows, for combinations based on two of our pupil groupings (disadvantage, and impact of disadvantage), the value added scores for each Key Stage combination.

While largest differences occur between KS2 and KS4, it is interesting to note that the gaps between pupils tend to widen more from Foundation Stage to KS1 than they do from KS1 to KS2 for the group most impacted by disadvantage.

And this is even more apparent if we take into account the number of years in each stage (two for Foundation Stage to KS1; four for KS1 to KS2; five for KS2 to KS4). The table below shows the value added scores calculated for each year or the relevant stage. This shows that the impact per year is highest between Foundation Stage and KS1.

### How much of the gap was present at the start of school?

It’s clear that differences in progress contribute substantially to differences in attainment by the end of KS4.

How much of that difference is there when pupils start school though? Take pupils who are long-term disadvantaged and in the high impact group – i.e. those most affected by disadvantage – as an example.

Their KS4 average grade in English and mathematics is 3.2; just over 1.6 grades below the national average for all pupils. At the same time, their average progress from Foundation Stage to KS4 is 1.1 grades below the average for all pupils. This means that around two-thirds of the attainment difference at KS4 can be explained by the progress they make from Foundation Stage to KS4 – with the remaining third already there by age five when the pupils are assessed for Foundation Stage.

Using data from the first of the two tables we can estimate the contribution made to attainment differences at KS4 by initial (Foundation Stage) attainment and subsequent progress through each Key Stage – shown in the chart below.