what country has the best education system 2018

A solid foundation
Finland had the highest quality of primary education in the world in 2017, with an index score of 6.7. The index runs on scale of one (low quality) to seven (very good). Switzerland, Singapore, the Netherlands, and Estonia rounded out the top five for countries with the highest quality of primary education.

The best countries for education ranking was based on the following factors:
Canada has been named the third best country in the world for education.

In the overall ranking based on the education systems’ absolute performance, Finland improved its rank to sixth from last year’s ninth position. The top performing countries are the United States, Switzerland and United Kingdom, followed by Sweden and Denmark.
According to the ranking, Finland has the fifth most favourable environment for higher education. Finland also scores highly in web impact and government expenditure on higher education.

References:

http://dailyhive.com/vancouver/canada-ranked-best-country-education-2019
http://www.studyinfinland.fi/news-events/finland-succeeds-higher-education-ranking
http://www.gov.uk/what-different-qualification-levels-mean