Spelling Tutor Trial Results

2018 Trial
Average Spelling Improvement 10.5 Months
Length of Intervention 3 Months
Research Design One group pre-test/post-test study
Age Range Y4 - Y9 (8 - 14 year olds)
Inclusion Criteria Pupils were all identified by their SENCO as having a spelling age of at least 12 months behind their chronological age
Result On average pupils’ spelling age improved by 10.5 months over the 3-month period.

The Ratio Gain shows Substantial Impact
No. of Pupils 53 pupils from 7 schools
Test Used Vernon Spelling Test

Research Date: 2018

Spelling Tutor is an online intervention for pupils aged 6 years and over to improve their spelling. It uses spaced repetition to ensure spellings are stored in the long-term memory and are easy to recall.

Pupils write words, from dictation, to practise their spellings.

In this trial Spelling Tutor was used every day for 10 minutes, over a period of 3 months. At the start of the intervention all pupils had a spelling age of at least 12 months behind their chronological age.

Key Conclusions

  1. On average pupils' spelling improved by 10.5 months, after playing for 3 months. Which is a gain of 3.5 months per month played.
  2. The intervention is suitable for pupils having English as an additional language.
  3. Pupils who played daily made the most progress.
  4. Feedback from teaching staff and pupils was positive. The pupils found it easy to play. They needed minimal input from teaching staff.

Improvement in Spelling Age after Playing for 3 Months

"The children that have used Spelling Tutor have absolutely loved it! We’ve found it particularly useful for our older children that have done all our other interventions to death."

Lesley Humphries, Ratho Primary

How secure is this finding?

The trial was carried out in 4 primary and 3 secondary schools. There was no control group to compare the data. 66 pupils, from 7 schools were identified to take part in the trial, with 53 completing it. Data was used by those pupils who had a quantifiable spelling age.

The trial asked for pupils to play every school day for 3 months. On average pupils completed 25 sessions.

The feedback from schools was positive. All these pupils had regular attendance, and none were in the early stages of English acquisition. They were all significantly behind in spelling despite the schools’ best efforts, including catch up interventions.

Pupils' spelling ages were assessed using the Vernon Spelling Test at the start and end of the trial.



Spelling Tutor is an online program for pupils from the age of 6 upwards who are struggling with spelling. The intervention focuses on spaced repetition, writing and pupil ownership of learning.

The intervention is in three parts and lasts for 10 minutes. It requires minimal input from teaching staff.

Background evidence

The notion that spaced repetition could be used for improving learning was first proposed in the book Psychology of Study by Prof. C. A. Mace1 in 1932: "Perhaps the most important discoveries are those which relate to the appropriate distribution of the periods of study...Acts of revision should be spaced in gradually increasing intervals, roughly intervals of one day, two days, four days, eight days, and so on."

In the 1960s, Pimsleur language courses pioneered the practical application of spaced repetition theory to language learning.

Since the development of computers, spaced repetition has been an accepted method of learning and recalling information.

Evaluation objectives

The primary research question was to identify the impact of Spelling Tutor intervention on the spelling ability of individual pupils over a 3-month intervention period. Pupils selected for the intervention started receiving the intervention after the Easter break. Their spelling age was assessed at the start of the trial. Pupils' spelling was measured using the Vernon Spelling Test.

The process evaluation explored the implementation and impact of the intervention.



This was a multicentre trial within mainstream schools in England. The trial involved 4 primary schools and 3 secondary schools. The SENCO worked with teaching staff to explain Spelling Tutor, and to set up the pupils in the program.


The selection criteria for pupils were:

  1. A spelling age at least 12 months behind their chronological age
  2. Regular attendance
  3. Not in the early stages of English acquisition
  4. Able to use a computer independently for 20 minutes

The age and year group of the pupils were left to the SENCO to decide.


Spelling Tutor is an online program for learners aged 6 plus who are struggling to spell. The intervention requires very little teaching support. This trial was for pupils who were behind in spelling by at least 12 months.

Pupils are required to play Spelling Tutor most school days. The intervention selects words for each pupil based on their ability. It then repeats words they have spelt incorrectly using a spaced repetition algorithm.


The outcome was improved spelling age, as measured by the Vernon Spelling Test.

The tests were administered and marked by the school and the data shared with Spelling Tutor.

Sample Size

Fifty-three pupils from seven schools were chosen to participate in the trial.

There was no control group for this trial.

Outcomes and Analysis


The aim of the analysis is to assess whether the Spelling Tutor intervention has had any significant impact on pupils' spelling, as measured by the post-intervention test scores.

The primary analysis examined the impact on spelling age and looked at gender and English as an additional language.

On average Spelling Age improved by 3.5 months for each month played.

English as an Additional Language

Improvements were seen by pupils who have English as a additional language. On average Spelling Age improved by 5.5 months for each month played.


Analysing the progress between gender shows that boys make more improvements than girls (4.46 RG: 2.83 RG).

Key Stage 3 Pupils

Spelling Tutor performed well with those pupils in Key Stage 3, with an average ratio gain of 2.64. It was well-received by these pupils.


Spelling Tutor is a low-cost intervention requiring minimal teaching support. Pupils enjoy the interaction aspect of the intervention and the requirement to mark their own work.

Progress is linked to the number of times played and, as with all interventions, commitment is needed from the school to run the intervention on a daily basis. Pupils who played daily made the most progress.

Once the intervention is complete, there is no requirement to repeat.

On average spelling age improved by 10.5 months after 3 months. Boys responded to the intervention slightly better than girls. It is suitable as an intervention for pupils with English as an additional language.

It is not suitable for pupils with severe SEND needs, such as those unable to work independently for 20 minutes at a computer. However, it is particularly suitable with pupils with dyslexia or auditory processing disorder.

Spelling Tutor works for primary and secondary aged pupils.