Educational Passages sells a 5-foot mini-sailboat kit loaded with sensors and a satellite transmitter. After building and launching the boat, students can track its progress (as well as that of other boats) on the organization’s webpage. Should your school not be near a coastal location, they will connect you with others who will launch your boat at sea.
Even if you don’t build one of their boats, their website contains a wealth of information on ocean currents and science. And anyone can track the fleet of boats at: https://educationalpassages.org/events/atsea/
Marco Antonio Firebaugh High School, in Lynwood, CA, US (outside Los Angles), launched their mini-boat “Fledgling Freddy” from the research vessel E/V Nautilus on October 18, 2021 in the Pacific Ocean half-way between Los Angeles and Hawaii. The last update was today (Aug, 3, 2022), so we can assume it’s still sailing.
Fledging Freddy’s story and on-going progress can be found here: https://educationalpassages.org/boats/fledglingfreddy/