Shanghai Jewish Centers are organizing seders for Friday and Saturday; the main Seder in Shanghai will be at the historic landmark Ohel Rachel Synagogue at 7pm on Friday. Prayers kick off at 6pm, so get there early. Tickets for non-members is 380rmb, and 180rmb for students and children, get pricing details and register here.
The second sedar will be held on Saturday, at 7pm at Intown Jewish Center (candle light starts at 6.50pm), costs 300rmb and 150rmb for students and children. They will be hosting in both the Shanghai Jewish Center (register here) and the Intown Jewish Center (register here).
Shanghai Jewish Centers is hosting passover seder in a few locations, this one at the Kerry Hotel starts at 175rmb, and go up depending how much you'd like to donate. The dinner will start at 6.30pm. RSVP and register here.
Kehilat is hosting a sedar for the second night of Passover on Saturday. It starts right at 6pm, but there will be kids activities before that start at 5.15pm. For nonmembers the dinner costs 500rmb, for children 100rmb and under 5 get in free. RSVP and register here.
If you're doing DIY passover you can get your Matzah at Kosher Mart.
Also here's a brief history of Passover (VPN) as famously told by the Rugrats.