Phone-call tutoring boosts math learning during school closures; UN-backed Equal Earth projection to update world maps

Overview

Nature Podcast covers two science stories from Nature's reportage: a randomized controlled trial using basic mobile phone calls to tutor primary students in math during school closures, and discussion of a world map projection update led by the UN to move away from Mercator toward Equal Earth.

Key insights

• One-on-one tutoring via phone calls yields larger gains than SMS nudges or no intervention, across multiple countries during 2020–2022.
• The intervention costs about $11 per child and could translate to roughly 3.6 years of high-quality schooling per dollar, though scale poses training and staffing challenges.
• Results varied by baseline education, with Uganda and the Philippines showing particularly strong improvements, highlighting the need for targeted deployment.
• Separately, the Equal Earth projection discussion shows the Mercator distortion problem, and the UN vote toward non-binding adoption as a catalyst for broader GIS education and awareness.

Overview

This episode of Nature Podcast explores two interconnected threads in science and society. The first is an education intervention conducted during COVID-19 school closures, using basic mobile phones to reach students with math content. The second thread examines a mapping controversy that could reshape geography education and digital navigation: a push away from the traditional Mercator projection toward the Equal Earth projection, supported by a UN General Assembly vote, though non-binding in nature.

Education during crises: mobile phone tutoring trial

Researchers conducted a randomized controlled trial to test whether a low‑tech, phone-based tutoring program could help students maintain or improve math skills after schools closed during the COVID-19 pandemic. The study reached students in India, Kenya, Nepal, the Philippines, and Uganda between 2020 and 2022, focusing on primary grades (mostly 3–5, with some 1–2 in Kenya). Students were assigned to three groups: a control group with no intervention, a second group that received SMS messages with simple math problems (nudges to engage with material), and a third group that received SMS plus a tutor‑led phone call to assess understanding and tailor subsequent tutoring. Importantly, the tutoring journey was individualized, with teachers adapting the content to each student’s current level.

The results were striking. Students who received phone calls showed improvements roughly three times larger than expected from prior educational interventions. In Uganda and the Philippines, there were notable gains, with some grade 4 students reaching proficiency levels similar to what would be expected of grade 5 students. The SMS‑only group also improved compared to the control, but the gains were markedly smaller than the phone call tutoring group. These findings reinforce the value of one‑on‑one interaction for skill development, even when resources are constrained and connectivity is limited.

The researchers also provided cost estimates. The intervention cost was about US$11 per child for one‑on‑one tutoring, and they argued that this could yield 3.6 years of high‑quality schooling per dollar spent. However, other education researchers cautioned that scaling such a model nationally would require training a larger pool of tutors and possibly employing NGO partners to deliver tutoring in batches rather than across the entire school year. The study is notable for its randomized, quantitative approach in a field where many efforts are qualitative, and for demonstrating that a scalable, low‑tech solution can deliver meaningful gains in crisis contexts.

The Nature Podcast team contextualized these results within broader debates in education policy. While the randomized trial design is a strength, concerns remain about teacher workload and burnout, especially during emergencies. The researchers behind the study emphasized that the tutoring need not fall entirely on classroom teachers; NGOs and training programs could supply tutors who can work in batches for short periods. The discussion also highlighted variability across countries, with baseline education and existing gaps shaping both the magnitude and sustainability of benefits. Taken together, the episode presents a nuanced view of how a relatively simple intervention could be deployed to protect and improve learning in low-resource settings during crises.

Mapping the world anew: Equal Earth projection

The episode then shifts to a mapping story. The familiar Mercator projection distorts landmasses toward the poles, exaggerating the size of places like Greenland while shrinking areas such as Africa. The Equal Earth projection has been proposed as a more accurate representation of land area, and a UN General Assembly vote (164–1, six abstentions) signaled a non‑binding move away from Mercator toward supporting equal-area mapping in education and digital navigation tools. The UN vote was framed as a symbolic yet potentially influential step toward broadening awareness of projection choices and their implications for how we view and teach geography.

Interviewees explained that no projection is perfect; the Equal Earth projection preserves area but distorts shapes to some degree, particularly at the map’s corners. Its adoption would not automatically rewire platforms like Google or Bing, given the non‑binding nature of the resolution. Nevertheless, the discussion underscored the value of exposing educators and the public to multiple map projections and the math behind them, integrating geographic information systems (GIS) into the wider research and education ecosystem. The episode framed this as more than a technical adjustment; it is an opportunity to foster critical thinking about how maps shape perception and knowledge about the world.

In educational and scientific practice, the Equal Earth projection could serve as a tool for teaching about projections, cartography, and data visualization, potentially spurring interest in geography information systems and related technologies. The coverage highlighted the broader implications for GIS literacy, navigation apps, and Earth science education, while acknowledging that non-binding agreements hinge on subsequent actions by policymakers, educators, and technology companies. The segment closes with a sense of cautious optimism about increasing awareness of projection choices and their significance for science communication and teaching.

Takeaways

Across the two stories, the episode foregrounds how low-cost, scalable approaches can address urgent challenges—whether by safeguarding learning in crises or promoting more equitable representations of the world in maps. It also emphasizes the importance of rigorous evaluation (as in the education trial) and critical literacy about visual representations (as in the Equal Earth projection discussion). The show invites listeners to think about how science policy, educational practice, and technology intersect to influence learning, understanding, and how we see the Earth.