But they lag behind Tanzania, Seychelles, Mauritius and Swaziland in reading skills, according to a report by a regional education coalition.
The Southern and Eastern Africa Consortium for Monitoring Education Quality study involved a sample of 4,436 Class Six pupils in 193 schools across the country.
It was aimed at testing maths and reading achievement in 15 countries of the regional bloc.
The Kenya National Examinations Council (Knec), alongside similar agencies in other countries, carried out the survey on behalf of the consortium.
Zambia, Malawi, Namibia, Lesotho and Uganda, in that order, were ranked the worst in maths where the pupils could not solve basic problems in the subject.
Malawi, Zambia, Lesotho, Mozambique and Uganda, again in that order, performed worst in reading skills.
“The quality of education in the 15 countries is still poor despite the cross-regional approaches that the governments have taken to improve standards,” the consortium’s regional boss Demus Makuwa said.
The consortium is a network of ministries of education whose aim is to promote education for all goals and the millennium development goals.