A pair of Grade 10 learners from Goa Science High School placed second in the Regional Science and Technology Fair held in Naga City last week, edging out entries from fourteen schools across Camarines Sur.
Their project, a water turbidity sensor assembled from a salvaged laser diode and a photoresistor, measures suspended sediment in the Hinagyanan River for under three hundred pesos of parts. Commercial units for the same job start at eleven thousand.
The pair spent the second semester calibrating the sensor against samples the municipal health office had already tested, then ran it every morning for six weeks through the tail end of the rainy season. The readings tracked the laboratory results closely enough that the barangay has asked to keep the prototype for the next monitoring cycle.
The research adviser credited the school's after-hours laboratory access, opened last year, for most of the calibration work. The team advances to the national fair in February.