This year's theme connects with Sustainable Development Goal 4 ("Ensure inclusive and equitable quality education and promote lifelong learning opportunities for all") of the 2030 Agenda for Sustainable Development, and with UNESCO's Education 2030 Framework for Action.
Language and understanding
The main issue is the importance of schooling in first languages especially in early grades, which research shows leads to better educational outcomes. The poster and other publicity quote a report that as many as 40% of school children receive instruction in languages they do not understand.
Forty percent is an astounding figure. Even something say half that would indicate serious shortcomings in long-term efforts to promote "education for all."
The natural response to call for education that children can understand, however, highlights other questions: why policies have not done better, how to deal with multilingual classrooms (where there are several mother languages), where to get resources for materials and teacher training etc.
But the first step is to recognition of the issues, which the IMLD theme will hopefully help to promote.
Give kids a head start: Teach children in a language they understand! https://t.co/xQmpvFB3aA #MotherLanguageDay pic.twitter.com/i2BZvtFmht— UNESCO (@UNESCO) February 17, 2016
The case of Zambia
One of many possible cases is the country of Zambia.
A recent brief on girls' education, literacy and numeracy by the Adolescent Girls Empowerment Program (AGEP) found:
Overall levels of literacy are quite low, with less than a third of younger girls and about half of older girls being able to read.Surprisingly, however, MOI (language) does not come up as being a possible contributing factor to such low results. (No comparison with boys' levels.)
• When looking at literacy levels by number of years of schooling attained, it appears that only in secondary school do girls starting developing meaningful literacy skills.
• Math skills are also low. Out of a maximum of 10 possible correct answers meant to be completed by those with four years of schooling, not even those with secondary school could complete more than 75% Results are similar for girls in both urban and rural areas.
Of course girls' education presents some challenges that go beyond curriculum - hence a project like AGEP. But even out of school, might the MOI be an issue to the extent that language could limit mothers' involvement in their daughters' education?
More broadly, shortcomings of English-only instruction in Zambia have been noted for all students. In 2005, for example, the Basic Education Teachers Union of Zambia called for science to be taught in local languages, but framed that mainly as a need in rural schools. A 2014 paper by Rebekah Gordon notes recognition of low reading levels in Zambia, as well as efforts at reform over the years (the paper also has some historical background).
Language - MOI - is clearly a factor in the quality of education and the learning outcomes in a multilingual country like Zambia, but finding the ways to make that right is not always as straightforward a matter as it might seem.