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No, this is on par for such devices. There is little to no file system mgmt for field devices or EDRs. Just write and write. The file table is always apart from the circular memory. The amount of capacity to report is a known hack performed long ago for USB memory sticks. This is the same thing in a different package. This is probably all one chip.

You can buy your own (some come with the circular write as an option) and although the capacity is probably truthful, you can put it in a hard drive case and sell it to all the fools you can find.

In conjunction with some powered USB hubs, some cheap A/D->USB devices ($50 per 8 channels), and some hacked-together AC current probes, a power monitoring system for every line into your breaker box.

Students can use these sensors to e.g. study the thermal characteristics of their own home or the school or perhaps a shop or restaurant and correlate them with outside temperature, sunlight, humidity, etc.. Rapid temperature changes can potentially identify inadequate insulation, and temperature fluctuations per se can point to substandard heating control.

You can also build (or buy) a compact solid-state temperature and accelerometer logger and mail those around the country to see what the ambient conditions of mail and parcels are. Once you show that this works, students (even in the range of 14-18) could conceivably land an internship with a local company to introduce a system that tracks conditions of their shipments. You can get USB-key sized temperature and humidity dataloggers for about 60$ from http://www.signatrol.com/ Too expensive for a classroom project perhaps, but potentially very interesting for commercial use.

There are electronic components (for about 2$ apiece) that act as sensors (for e.g. temperature, humidity, air pressure, light, CO2 concentrationt)(see e.g. http://martybugs.net/electronics/tempsensor/ , http://www.tempsensor.net/) .

Attach those to a low-power radio transmitter, and add a transceiver to the USB port of a netbook and you get an interesting wireless sensor network.

Basic ready-made dataloggers can be had for as little as $25 (see http://www.dataq.com/products/startkit/di194rs.htm) and you can get ready made chart display software for them plus APIs in Visual Basic, C++ etc.. They also give away one of those per month, but I consider that a publicity stunt I wouldn't want to expose kids to. An alternative is a microcontroller board can be found for $40 (see http://al-williams.com/app4kit.htm).

Building and testing the sensors from components could be a 1-semester project. Dataloggers are a more complicated proposition, and require some more electronics knowhow, but even that can be done by 15-18 year olds in one semester. Otherwise writing the data-capture software is an option too, but I'd add a full semester for that.

For giving credit I have no other suggestions than to ask for either a final report upon completion or (for additional credit) bi-weekly reports (for preference in Open Office of course, with photographs of the equipment, the measurement setup, and spreadsheet graphs showing the data) for which you provide a template.

I'm a believer in letting students submit bi-weekly progress reports in memo form (so you can see what they're doing, help them where needed, and prevent them from wasting time on dead ends and blind alleys), and then asking them to use these memos when preparing a final report. That way students learn to what progress reports are, why it's important to be able to state clearly what you've done, and how such memos can be used to spread the burden of reporting across the project. Besides which, this is how it's done in professional practice too.

As to the final report: if you provide, say, three templates with varying levels of complexity (from a 2-page leaflet to a full report with problem definition, background physics (with proper references), measurement setup, data description (data in an appendix of course), summary and conclusions, you can provide a different amount of credit for each type of report.

There are several inexpensive (under $200) data loggers available. For example, the HOBO, or something from the Datalogger Store. Dataq also sells inexpensive A/D converters, but you would have to take a laptop along on the rowing shell to record the data, Their stand-alone data loggers are a bit more pricey ~$400), but use SD memory and have high resolution and high storage capacity. You can get free samples of accellerometers from Analog Devices .

I think you might be able to get started with a DATAQ WinDaq starter kit. Specifically, the DI-194 is only $13 + S&H for a four-channel, 8-bit DAQ that you just plug into your serial port.

I think you might be able to get started with a DATAQ WinDaq starter kit. Specifically, the DI-194 is only $13 + S&H for a four-channel, 8-bit DAQ that you just plug into your serial port.

To translate the input of a device with a varying voltage (Pressure, temperature, etc transducer) we use a little device from Dataq www.dataq.com part number DI-194 which converts the signal into a serial stream. This device has 4 channels so it can be hooked up to more than 1 sensor. Then we use a radio modem from Freewave www.freewave.com which is expensive but incredibly robust and reliable. These modems do NOT need a license as long as their output power measured at the antennae is under 1 Watt. The pre-built modems are very expensive but the OEM modules are cheaper if you want to build your own box with the DI-194 inside which is what we do.