The Northern Virginia Youth Symphony Orchestra will present its second concert of the season tomorrow at Lake Braddock Secondary School's Little Theater, 9200 Burke Lake Rd., Burke. The orchestra, under the direction of Luis Haza, will perform "Nature Life, A Symphonic Poem," by Andreas Makris, a former composer in residence of the National Symphony Orchestra. The program will also include the Overture to William Tell by Rossini, Bolero by Ravel and Schubert's Unfinished Symphony.

Concert tickets will be sold at the door for $4 per adult and $2 per student or senior citizen. For further information, call 356-2666.

*At West Springfield High School, "Dessert With the Madrigals -- A Christmas Concert" will be held on Saturday at 7:30 p.m. The madrigal singers, an a cappella group of 24 West Springfield High School students, will sing a variety of Christmas music. This group sang at the White House Christmas Party and will leave for Italy Dec. 26 to participate in the Rome Festival and appear before His Holiness Pope John Paul II. Tickets are $4 per adult and $2 per child 6 years and younger. Ticket prices include dessert and may be purchased from any madrigal singer or by phoning for ticket reservations. To reserve yours, call 451-4926.

*Hispanics United of Virginia (Hispanos Unidos de Virginia) is offering evening classes in construction and remodeling, computers: basic language and COBOL, carpentry, and satisfying requirements of the General Equivalency Diploma (GED). For further information, call 533-9300.

*The Housing Expense Relief Program reminds Fairfax County residents that grant applications must be filed with the Office of Assessments by midnight, Dec. 31, 1985.

This program provides up to $150 per year in grants to qualifying low income homeowners or renters between the ages of 55 and 64, and to low income homeowners or renters of any age who have minor children living at home. To qualify, an applicant must have an annual gross income of no more than $10,000, excluding the first $4,000 income of each relative other than the spouse residing in the household. In addition, the combined financial net worth of the applicant and spouse living in the household may not exceed $35,000, excluding the value of the home, if owned, and up to one acre of land around it.

Citizens living in subsidized housing or receiving public welfare assistance are also not eligible. For further information, call 691-2437.

*Calling all Tech-ies: The Northern Virginia Chapter of the Virginia Tech Alumni Association is hosting an alumni Christmas Party Saturday from 8 p.m. to midnight at the Country Squires Restaurant in Seven Corners, at Leesburg Pike and Patrick Henry Drive.

Admission is $10 per person. There will also be a cash bar. Formal dress is requested. For more information, call Otto Guttenson at 573-5314 or Cassandra Rich at 430-9323.

*Registration for winter and spring classes sponsored by the Vienna Parks and Recreation Department began Dec. 16. Classes offered include children's arts and crafts, aerobics, tennis and gardening, plus special courses like oriental rug appreciation, amateur radio training and square dancing. Vienna residents over 65 years may register for most classes free. Class brochures and registration forms are available at the Vienna Community Center, Vienna Town Hall, and the Patrick Henry Library. For more info., call 938-8000, ext. 277.

*The Arlington Young Democrats will host their annual holiday party at 8 p.m. Saturday at 700 N. Illinois St., Arlington. Guests are requested to bring a contribution for the Toys for Tots campaign. For more information, call Judy Wheat at 522-5388 or Greg Principato at 931-3274.