The teacher used an alias.

The students carried no books.

The classroom was papered in cheap red velvet.

As each person entered the room they paid $15 -- in cash -- to a soft-spoken woman with teased red hair.

It was not your typical night school.

But that didn't seem to bother the 30 Northern Virginia students, who ranged from people in their mid-20s to retirees. All had answered a newspaper ad urging them to come to the Tysons Corner Holiday Inn and "Win Next Time You Go to The Casino."

"You gonna teach us how to win, Bill?" one student asked anxiously.

"Let's put it this way," answered Bill Johnson with a grin, "I'll teach you how to lose less."

With that, Johnson launched into a 2 1/2 hour dissertation on how to beat the casino odds.

Johnson, who describes himself as a professional blackjack player turned gambling instructor, refused to tell the students his real name. The students were just as reluctant to tell him theirs. Johnson says he still works as a professional gambler and would jeopardize his career at the tables if it became known that he was good enough to be passing on his gambling tips to others.

The first thing Johnson did was survey the class for their favorite games. Red-faced students admitted they regularly play the wheel of fortune and slot machines.

They were chagrined when Johnson told them those were the two games with the worst player odds.

But blackjack won top honors as the game everyone had played.

"A couple of years ago craps was the big game," Johnson explained >POKER, From Page 1> on the telephone before class. "But you wait and see, most people play blackjacket. It's the most popular casino game in the country."

The reason became apparent at the opening of the class.

"Blackjack is the only game which can be beaten," Johnson tells the class at the outset.

Next Johnson asked the students, whom he affectionately called "gamblers," where they play. Most said nearby Atlantic City and Nevada.

Allowing his own preference to surface, Johnson told the class it was worth their while to travel to Nevada rather than frequent New Jersey's resort where: "The rules are lousy, the games are lousy and they're skinning you."

Johnson chastised the New Jersey casinos for using six decks of cards at every blackjack table, while Nevada has several casinos using two deck games. (Professional gamblers prefer tables using the least number of cards because it is easier to keep track of which cards have been played.)

Johnson, one of eight gambling teachers with Scientific Systems in Joliet, ILL., teaches two mini-seminars a month in the Washington area. Half of the class deals with odds and betting strategies on various games and the other half outlines a basic system for blackjack.

The last 20 minutes of the seminar are spent plugging a weekend blackjack seminar -- which costs $595 and purports to teach serious players how to count cards. The pamphlet on the course says successful card counters can make up to "$500 a day."

Card counting is a technique blackjack players use to keep track of every card played and every card remaining, even in multi-deck games. Card counting is technically prohibited by casino managers, but since it is impossible to tell for sure if a player is lucky or card counting, professional gamblers are usually able to play undetected.

The key to card counting without tipping off the casino, says Johnson, is to look like you're losing when you're actually winning, Johnson said players should win a bit in one casino and leave. If a player gets too greedy, he warns, the management will ask the gambler to leave.

Johnson says he is able to play like a professional while looking like "Tommy Tourist," although he admitted that one time he was asked to leave a casino in Lake Tahoe -- because he made a stupid mistake. Johnson refused to describe the mistake.

"One question people always ask me is 'If you can win $500 a day playing blackjack why aren't you out there now,'" Johnson said, anticipating the question. "Well, there are only two states where you can gamble in the United States and there just aren't enough casinos to play in without becoming known.

"So, every five or six weeks I fly out to Nevada for a few weeks."

The object of Jonson's class was to provide people with a relatively simple blackjack system they could memorize and use in casinos.

Johnson also issued a stern warning against a popular betting method known as "double up to catch up," where players double their bets everytime they lose a hand.

After demonstrating how quickly a gambler will be chasing a $5 bet with $1,000 Johnson sid, "If you don't learn anything else here tonight, you got your money's worth if you come out knowing that 'double up to catch up' doesn't work."

As the class filed out of the room, most agreed that the $15 investment had been worth it.

One man, who identified himself as a local attorney and professional poker player, said the class was "useful."

Another student, a computer analyst, said he was taking the course because he was going to Atlantic City for the first time this summer.

One older woman, who says she regularly hops aboard the bus from Washington to Atlantic City, said jokingly she was going to tell her "women friends" about the class so they could go to the casinos and "put those Social Security checks to work."