A widening gap is emerging across Kenya’s senior schools, with institutions attracting the highest-performing learners also recording the biggest class populations, while schools in lower categories continue to operate with fewer learners and weaker access to key facilities, a new survey shows.
The 2026 Senior School Survey by Usawa Agenda found that Cluster 1 institutions have considerably larger classes than Cluster 4 schools. In Form Two, a typical Cluster 1 school has 60 learners in a stream, while the figure drops to 56 in Form Three and 55 in Form Four.
The corresponding numbers in Cluster 4 schools are 43 learners in Form Two and 40 in both Form Three and Form Four.
The difference is even clearer when the number of streams is considered. Cluster 1 schools have an average of 8.1 streams per class, compared with 4.7 in Cluster 2, 2.7 in Cluster 3 and 1.8 in Cluster 4.
Private schools recorded the lowest class sizes, with an average of about 30 learners in each stream across Forms Two, Three and Four.
Yet, the larger populations in Cluster 1 schools have not stopped them from posting stronger academic results. According to the survey, a learner enrolled in a Cluster 1 senior school was more than eight times as likely to achieve a mean grade of C1 and above in the KCSE as one attending a Cluster 4 school.
The findings are contained in a survey covering 1,344 senior schools across the country. The institutions assessed included schools in Clusters 1, 2, 3 and 4, private schools and special schools, with principals serving as the main respondents.
The survey also found that Cluster 1 schools give learners a wider selection of subjects. They offer an average of 15 examinable subjects, while Cluster 2 schools provide 13, Cluster 3 schools 12 and Cluster 4 schools 11.
This gives learners in the higher-category institutions more options when deciding on their preferred career pathways.
The difference in enrolment can also be seen in the number of candidates presented for national examinations. A typical Cluster 1 institution had 359 candidates sitting the 2024 KCSE, compared with just 73 candidates in a typical Cluster 4 school.
Despite handling larger numbers, Cluster 1 schools were found to have a stronger supply of facilities and services.
The survey shows that 89.8 per cent of Cluster 1 schools have working computer laboratories, against only 18.6 per cent of Cluster 4 schools. Computer lessons are available in nine out of every 10 Cluster 1 schools, compared with just one in five Cluster 4 institutions.
There is also a major difference in library access. Operational libraries are available in 79.3 per cent of Cluster 1 schools, while only 29.1 per cent of Cluster 4 schools have such facilities.
Teacher availability also favours the top category, with Cluster 1 schools having more than three times the number of teachers per examined subject compared with Cluster 3 and Cluster 4 schools.
Learner retention presents another area of concern. Cluster 4 schools recorded a dropout rate of 3.4 per cent, the highest among the categories, while Cluster 1 schools recorded the lowest rate at 0.5 per cent.
The survey also compared dropout rates according to the gender composition of schools. Mixed schools recorded the highest rate at 3.2 per cent, followed by boys’ schools at 1.9 per cent and girls’ schools at 1.1 per cent.
According to the report, the findings point to continuing inequality within Kenya’s senior school system. Cluster 1 institutions generally have stronger resources, while Cluster 4 and special schools face greater limitations.
The gap is also reflected in health services. About 89.1 per cent of Cluster 1 schools have a sick bay, sanatorium or clinic, compared with just 4.6 per cent of Cluster 4 schools.
Medical personnel are available in 96.3 per cent of Cluster 1 schools, meaning nearly every institution in the category has staff to provide medical support.
Cluster 1 schools also perform better in several areas of school safety. They have the highest share of institutions carrying out fire drills and maintaining specific fire assembly points. However, the report says preparedness for emergencies remains uneven across the country.
The schools also recorded better outcomes in the regression analysis.
The survey further found a strong link between school type and examination performance. A learner in a boarding school was more than two-and-a-half times as likely to score C1 and above as a learner in a day school.
However, the report warns that the difference should not simply be blamed on whether a school is a boarding or day institution. It points out that the marks learners obtain before joining senior school are closely linked to the type of institution they eventually attend.
Candidates who sat the 2024 KCSE from Cluster 1 schools had an average KCPE mark of 362, compared with an average of 242 among candidates from Cluster 4 schools.
The survey comes at a key stage in Kenya’s shift to competency-based education. It is the first senior school survey released after the first group of CBE learners entered senior school in January.
While the new system is now in operation, the report says the first transition was less than seamless and draws attention to difficulties surrounding the placement of learners.