Tempelhof is a really great destination. I've been a couple of times and I'd thoroughly recommend it to anyone. BUT... it's about 6 hours each way in your average spam can. The first time I went it was out on the Saturday and back on the Sunday in a Grumman Tiger and it was a pretty long slog.
If you fancy something different, non-French, and a bit closer then either Maastricht or Antwerp are both worth a visit and quite feasible for a weekend trip.