In general, your legs should really be "lively" the last few weeks of the season, if you're peaking well. Individuals respond differently, but dead legs are not (in general) an encouraging sign. Two things that can help you through, though:
1. Agreeing with the posters above, avoid making major changes in your routine at this point. If your legs are heavy your reserves are probably close to depleted. Don't present your body with yet another stimulus that it has to adapt to. (And, yes, a huge cut in mileage would be one example of such a new stimulus.)
2. This time of year can be tough for students because there are academic stresses (including disrupted schedules), as well. Jumbo Elliot (sp? the late Villanova coach) said it best: "Live like a clock." In the last weeks of the season, when you are adapting maximally to the stress of training/racing, you just don't have the reserves to adapt to other stressors like an irregular schedule.
In particular: Commit yourself to getting a full night's sleep every night, basically going to bed and getting up at around the same time each day. (And that includes the weekend days.) NOTHING HELPS DEAD LEGS BETTER THAN SEVERAL NIGHTS OF GOOD SLEEP. There's a lot of debate about whether you need a good night's sleep the night before the big race, or the night-before-the-night-before. How about you focus on good sleep the whole week before?
In line with this: A lot of people have favorite "stress foods"--stuff they particularly eat/drink when feeling stressed. Caffeinated drinks and chocolate (which also has caffeine) are two biggies in this category. Resist the temptation to load up on caffeine/chocolate when feeling stressed, because they'll only disrupt your sleep more.
And yes, I realize this is an old thread, but I think it's still timely.