This coursework can be quite tricky but is easy enough if you can get it started. The best places to go to are Wiki as it provided an excellent source of information for my plan. I would recommend things to include such as the theorized phototaxis of a maggot, the taxonomic groups (only up to the genus is really necessary) of the maggot, the life cycle of a maggot (larval and pupating stages). With the experiment, I would recommend the procedure you have stated. It provides decent results but I would include a light meter to measure the lux (light intensity), a dark room to prevent any other sources of light interfering, a water tank to absorb the thermal energy emitted by the lamp (you're measuring the phototaxis, not thermotaxis), place the lamp to one side and not above the maggot, draw a circle split into 4 (two 120 degree sections and two 60 degree sections (If it moves towards the light it is photo positive, away= photo negative, either direction= neutral)). I wouldn't suggest timing it because it may take too long. Take about 20 maggots and see which direction they head to. If you do a Chi- squared test afterwards, then you can still end up with a conclusion even if your results seem random. Hope this helped.