SOME DOGGONE unusual dogs will be on hand this weekend at a rare-breed show in Washington.
About 700 rare breeds are expected on the mall at the Museum of Man for the two-day Cherry Blossom Classic sponsored by the American Rare Breed Association and Kal Kan's Pedigree dog food manufacturers. Entries will include these eight rare breeds making their American show debut: the Karelian bear dog, Carolina dog, New Guinea singing dog, Coton de Tulear, American Indian dog, petit bleu de Gascogne, Appenzell mountain dog and the Caucasian Ovatcharkas.
Other rare breeds expected are the Shar Peis, Australian shepherds, the hairless Xoloitzcuintles and Peruvian Inca Orchid. Rare breeds are not registered with the American Kennel Club, but they have been established with a breed standard of conformation and recognized by a smaller registry than the AKC.
The Chinese crested, for instance, was shown as a rare breed for many years until this year when it was accepted to the AKC registry.
Bill Berloni, known as the dog trainer to the stars, will make special appearances and will be available for dog talk.
Show hours are 9 a.m. to 4 p.m. daily. The mall is at Independence Avenue and 4th Street N.W., at the west front of the Capitol. It is free. Details: show chairman John Slack (202) 722-1232.
* A dog needs a home. Janet and John Yeske have found a large, friendly and beautiful dog that is predominantly black with some tan. He looks like a German shepherd with floppy ears. The Yeske family has had him since January but
cannot keep him and wants him to have a good home. Janet Yeske says the dog should be with children. ''He is so gentle with our 8-year-old it is unbelievable, and the fact that he loves children so much, it would be nice although a good loving home is most important,'' she says. Call the Yeskes at 298-4549 after 4 p.m. if you can offer this dog a loving home with responsible owners.
* Spay your pet. Those who need reduced-cost certificates for spaying and neutering their pet should call SNAP (Spay and Neuter All Pets) at 484-2020. SNAP was founded by B.J. Small.
* Pets on Wheels' annual benefit gala will be 7 p.m. to 1 a.m. on May 31 dockside on board the Lady Baltimore. Called Bon Voyage, the event costs $50 per ticket and includes food and drink plus entertainment on all three decks. An auction will be held, and anyone wishing to donate items for the auction, reserve tickets or obtain other details can call 396-1762.
Also, Pets on Wheels needs volunteers to work from 1 p.m. to 5 p.m. May 5 at their booth at the Baltimore Bureau of Animal Control's pet show at the shelter in South Baltimore and from 10 a.m. to 3 p.m. May 11 at their booth at the S.P.C.A. Animal Fair at the shelter on Falls Road. Call 396-1762.
* The Maryland Forum for Animals is dedicating April 22 to April 28 as ''World Laboratory Animal Liberation Week,'' with many events planned. For complete details, call Tony Promutico, coordinator, at 536-0643.