Louis Tyler, 7, doesn't know why he was on strike -- nor does he know what a strike is.

Nevertheless, he and a dozen other shouting children were carrying cardboard signs taped to sticks yesterday outside the Randolph Hills Activity Center in Rockville to protest what they called "rotten" treatment by the Montgomery County Recreation Department during the summer program, which ends today.

Tyler said he joined the strike because he and his 5-year-old sister, Dixie, had nothing better to do and because he and the others are "fed up" with the recreation department.

The department charges a $10-a-summer fee for each child to participate in the seven-week playground program, one of 50 in the county. Extra charges are imposed for special trips to bowling alleys and swimming pools.

The children, ages 5 to 14, said yesterday that they just hadn't been getting their money's worth.

They said they planned to abstain from games and arts and crafts all day by way of protest. But by 1 p.m., a recreation department supervisor, Cindy Gorman, ordered them to drop their signs and return to games of kickball and a scavenger hunt or else go home.

The young protesters said they had felt the last straw Wednesday, when 19 of them paid $1.25 to swim at the new Upper County Pool in Gaithersburg but were stranded in Rockville in the heat and humidity for two hours until the bus driver remembered to get them. By the time they got to the pool, it was too late to swim, they said.

Yesterday, recreation officials returned the swim money to the children, but the strikers said they weren't satisfied.

"This isn't the first time something like this has happened," said Mabel Pinedo, 10. "When we go places, most the time the buses come late, and we don't get our money's worth. It's rotten."

Alan Nemith, Randolph Hills summer director and a senior at the University of Maryland, said the children have had some legitimate complaints about services not rendered by others in the recreation department. He said he has complained to his area supervisor without success.

Nemith said he suggested the idea of a strike to the children, and they made signs Wednesday night.

"This is the first complaint I've heard about," said Jean Peyton, director of the department's eastern area. "None of the children have ever articulated any concerns to me before. . . .If they are upset, then I've got to hear from them."

Darald Lofgren, chief of programs for the department, said it was the first complaint he'd gotten about the playground program.

While it all ends today, the children said that they will return next year to see if the situation improves -- and because they have nothing else to do during the summer.

"It's better to come here than stay home and watch TV," said 10-year-old Sandra Arzabe.