The official guide to Rio de Janeiro Carnival is live (carnaval2014.rioguiaoficial.com.br, in Portuguese). A bit of deduction work in figuring out the information will be worth it, guaranteed: it's all here - the Special Group, Access Group, and Children's samba schoos (Escolas Mirins) parades at the Sambódromo on Avenida Marquês de Sapucaí, and blocos, or street Carnival groups, grouped by region. About 400 blocos signed up with the Rio de Janeiro city administration this year.
Look up Agenda for the full schedule, click on each item to open a window with place and time (military) for each parade. Pre-Carnival is in full swing!
Besides parades, there are free parties. Cordão do Boitatá, for example, is commemorating its 18th anniversary with "Esquenta nos Prazeres". The esquenta (literally, a 'warm-up', meaning a pre-Carnival event), is on Mondays through the 17th at Morro dos Prazeres, a community with a UPP (Police Pacification Unit).
Dozens and dozens of esquentas are in Zona Sul, near most hotels. Banda de Ipanema is turning 50. They rehearsed today at Praça General Osório (photo below) and will rehearse next on February 15 at 5:30 p.m. on the corner of Rua Jangadeiros and Rua Gomes Carneiro in Ipanema.
Some groups throw parties requiring tickets - Spanta Neném had a big rehearsal today and will have a post-parade and masquerade still, but their Lagoa Rodrigo de Freitas desfile (parade) and that of Spantinha, for the kids, are free.
Then there are the blocos in Centro and the Port Zone, in Grande Tijuca and other districts in the North Side, and more. Look for updates and news on some of them on the Rio Carnival Guide.