Nancy didn't hesitate. She jumped into her Mustang and broke her own personal record for getting under way. Soon she spotted the car several blocks ahead. It was turning left onto a side street. Nancy followed as fast as the law allowed.

At the side street, she made a racing turn and sped down the winding, tree-lined avenue, the red car still far ahead of her.

Nancy pressed down on the accelerator. Her blue Mustang responded instantly, and the gap began to narrow. They were heading into Sally Lane's posh neighborhood. The street went down a little hill and curved to the left before straightening out. As Nancy came out of the curve, she muttered, "Oh, rats!"

The street was empty as far as she could see. Somehow Kim had given her the slip.

Nancy braked to a screeching halt. The car couldn't have gotten that far ahead in the few seconds it was out of sight. It must have turned into one of the driveways.

She began to move again, at little more than walking pace, pausing to peer up each driveway. At the fifth one she got lucky. She could just see the back fender of a red car, sticking out from behind a trellis of vines. She pulled over and parked just beyond the driveway.

The redbrick house was very large, with white shutters, and was set well back from the street. Matching oak trees flanked the brick walk that led to the front door. Nancy walked up to the door. The name engraved on the bra.s.s door knocker was Archibald. Hadn't Sally told her Kim's last name was Foster, or-Forster, yes, that was it.

Nancy pressed the mother-of-pearl bell to the right of the door. After a few moments a middle-aged woman with gray hair, wearing a navy blue dress and two strings of pearls, opened the door.

"If it's the Junior League raffle," she began, "I'm afraid I've already-"

Nancy smiled politely and said, "No, ma'am. I'm looking for Kim."

The woman raised her eyebrows. "Kim? Oh, yes, of course. You must be one of her school friends. It's around the back, dear. Over the garage."

Nancy thanked her and went in the direction the woman had indicated. At the back of the house, separated from it by a high hedge, was a two-story brick garage with s.p.a.ces for four cars. A wooden staircase led up to a second-story door on one side. Nancy climbed the stairs and knocked.

No one answered, but Nancy was sure she heard someone stirring inside. She knocked again, louder, then called out, "Kim? I have to talk to you."

There were more rustling sounds, then the door swung open. Kim stood there obviously defeated, the black wig in her hands. "Come on in," she said, "before Mrs. Archibald hears you."

Nancy followed her into a small but comfortable living room. On a table between two windows was a large photo in a silver frame. The picture showed a younger and happier Kim seated between a man in a dark suit and a woman in a black dress. Apparently her parents were the housekeepers for the Archibalds.

Seeing where Nancy's attention was focused, Kim rushed over and turned the photo facedown on the table. "Why don't you stay out of my life?" she cried.

"I'm afraid I can't," Nancy told her. "Kim, what were you doing at the bank?"

"Just what you said," Kim shot back hotly. "Why can't you leave me alone?"

"What I said?" Nancy echoed, very confused.

"I haven't kept a single penny of it for myself, and you both know it," Kim continued.

Nancy simply stared at the girl. What was she talking about?

"Kim, listen to me," Nancy said. "I'm a detective. Whoever you think I am, you're wrong. My real name is Nancy Drew. The reason I'm at Brewster is that someone on the board of trustees asked me to find out who is responsible for the grade-changing racket. And I'm pretty sure you can help me."

"Oh, su-u-re," Kim replied, rolling her eyes. "This is a test, right? To see if I can be trusted? Don't worry. I'll live up to my end of the bargain." With that, she collapsed into a chair and began crying bitterly.

Nancy waited until Kim calmed down and straightened in the chair, wiping the back of her hand across her cheeks. "I guess that's it, huh?" Kim told her. "Now you'll lower my grade-point average, just the way you said you would if anything went wrong. I can kiss college goodbye."

Nancy went over and held Kim by the shoulders. "Listen to me! I am not not the person responsible for this. I swear! You've got to tell me what's going on, Kim. It's the only way I can help you." the person responsible for this. I swear! You've got to tell me what's going on, Kim. It's the only way I can help you."

Kim stared up into Nancy's eyes. "Are you for real?" she finally asked.

Nancy nodded.

"I was so sure you had to be involved. I just couldn't see Victor running this on his own," Kim continued. "He loves fooling around with the school computer and getting it to do weird tricks, but once he's figured something out, he gets bored and goes on to something else. He couldn't be bothered to do the same thing over and over, not even for money. So I figured he had to have a partner. Then you showed up, and I was sure."

"If Victor did did have a partner, it would be someone at the school," Nancy pointed out, perching on the edge of the sofa. "But I've only just started there, and this grade-changer has been operating for almost two weeks. Besides, what makes you so sure Victor's involved?" have a partner, it would be someone at the school," Nancy pointed out, perching on the edge of the sofa. "But I've only just started there, and this grade-changer has been operating for almost two weeks. Besides, what makes you so sure Victor's involved?"

Kim stared down at her lap and said so softly that Nancy had to lean in closer to hear, "He told me so. He said that he'd changed someone's grades. He pretended to feel really bad about it, but now I can see that was just a put-on. If he'd meant it, he wouldn't have kept doing it, and he wouldn't have forced me to get involved."

Nancy's breath caught in her throat. "Why did you write that note to the headmaster?" she asked after a pause. "It was you, wasn't it?"

"Sure. I was furious at you and Victor for what you were doing to me," Kim replied, her pale blue eyes flashing. "I wanted to get you in as much trouble as I could without getting myself in hot water. It didn't work, did it?"

"It might have," Nancy told her, "except that Mr. Friedbinder knows who I am and why I'm at Brewster. How did you get involved in this racket?"

"There was a message in my E-mail," Kim explained. "Whoever sent it knew I couldn't afford to pay to have my grades changed, but he said I could improve my transcript if I ran a few errands. He also said that if I didn't agree, my transcript could end up looking a lot worse than it really is. So I opened the account wearing this dumb wig. And he tells me when to pick up the money."

"Why didn't you go straight to the headmaster and tell him about it?" Nancy asked.

Kim shook her head sharply. "I couldn't bring myself to turn Victor in. I'm really hung up on the guy."

"Victor's not the only one who could be responsible," Nancy told Kim. "If I'm going to catch the culprit, I need to know how the money transfer works. I know you have a bank card for that account, but how do you know when to use it, and what happens to the cash?"

"I get an E-mail message," Kim replied. "In code. If it says M five, I know I should withdraw five hundred dollars on Monday. T ten means one thousand dollars on Tuesday, and so on. It's usually after or before school, but today the message said to go at lunchtime. I'm missing math right now."

"How do you deliver the money?" Nancy asked.

"I put the bills in a brown envelope and leave it in one of the faculty mailboxes before school."

"What?" Nancy exclaimed, straightening up. "Which one?"

Kim shrugged. "It's not labeled. It's on the bottom row, on the side near the door."

Nancy frowned and stared into s.p.a.ce. Then she said, "I'm going to need your help to put the person behind this out of business. How about it?"

Kim nodded hesitantly.

"Great," Nancy continued. "Now, here's what I have in mind. I want you to deliver the money you picked up today."

"You do?" said Kim incredulously.

"Yes, I do," Nancy replied. "And then I want you to stay home from school for the next two days. Think you can play sick for that long?"

"No problem," Kim said. "No problem at all."

At eight forty-five the next morning Nancy was standing near the coffee urn in the faculty lounge, paging through a news magazine. She glanced up just as Kim came in, stuck a brown envelope into a mailbox on the bottom row, and scurried out.

More and more teachers were drifting in, checking their mailboxes, and getting coffee. Each time one of them blocked Nancy's view of the mailboxes, her anxiety level soared. She longed to move closer, but she didn't dare. The person behind the racket knew Nancy's real reason for being at Brewster-the threatening message in her E-mail proved that. If she was seen too near the mailboxes, the culprit would sense a trap and leave the envelope with the money where it was.

Nancy straightened up and felt her pulse beat faster. Dana has just walked into the room and paused near the mailboxes. Was this the pickup?

But then she turned and headed straight for the coffee urn. The envelope was still in place. "Hi, Nancy," Dana greeted her. "How are you getting along with the computer system?"

"So far, so good," Nancy replied. "You're here early. Is there a problem?"

Dana smiled. "No, no. Not this time. I have an appointment near here in a little while, and I thought I'd stop by to make sure the computer beast is behaving itself."

Nancy smiled back distractedly. She was very aware that Dana was blocking her view of the mailboxes. She made a half-step to the right, but Dana moved in the same direction and began asking her about tutoring. She wanted to know if Nancy had thought of using the computer system.

If she could have, Nancy would have pushed Dana aside. She had had to see that mailbox. to see that mailbox.

Slowly Nancy angled to the left. Again, Dana adjusted her position so that she was blocking Nancy's view. This is unbelievable! Nancy said to herself. Was Dana moving on purpose? It didn't seem so because she kept talking excitedly about the applications of the computer in tutoring.

Nancy was about to explain that she wasn't in charge of the program, when Friedbinder entered and paused to survey the room. When he saw Dana and Nancy together, he scowled and turned his back on them. A moment later Phyllis came in. She, too, noticed Dana and Nancy. She gave Nancy a quick nod, then turned to Victor, who had appeared at the door to speak with her.

Dana, her back to the door, missed all this. As the nine o'clock bell rang, she said, "Oh dear, I'd better run. We'll talk again about coming up with an interactive approach to tutoring. I really think it's the way to go."

Heading for the door, Nancy looked at the mailboxes and drew in a quick breath. The brown envelope was gone!

Chapter Eleven.

NANCY CONTINUED in the direction of the door, fighting down an impulse to break into a run. How could she have let someone make off with the envelope, right under her nose!

Pausing outside the door, Nancy peered up and down the hall. To her left she saw a girl in jeans and a T-shirt, with books under her arm. To her right was Phyllis Hathaway, just going into the administration offices. She was too far away to see if she had anything in her hand.

The trap had failed, that was obvious. The question was, why? Was it an accident that Dana had blocked Nancy's view at the crucial moment, or had she done it on purpose?

If it had been a coincidence, then it was just a piece of bad luck. If not, it meant that Dana and Phyllis were guilty and and that they knew Nancy was trying to trap them. The only way they could have known that was if Kim had told them. that they knew Nancy was trying to trap them. The only way they could have known that was if Kim had told them.

Nancy shook her head. Stop jumping to conclusions, Drew, she told herself. Walter Friedbinder and Victor had also been near the mailboxes. Either of them could have made off with the envelope, too. She would simply have to come up with a new plan for trapping the guilty party.

"Hi, there," someone called. Nancy turned and saw Randi coming down the hall toward her.

"I looked for you yesterday," Randi continued. "I still want to do that interview. Are you free at noon?"

Nancy decided it was time to be direct. "Randi, yesterday you called me Nancy Drew. How did you know my name?" She watched Randi's face carefully. The threatening message had been sent from one of the terminals in the newspaper office after all. That fact alone put Randi in a very select group of potential suspects.

Randi rolled her eyes. "Oh, come on! It's not such a big deal. I was just goofing on you yesterday. Can you blame me, after that art show story you gave me? Of course I know who you are. I'm a journalist, right? I read the River Heights papers every day. I've seen your name and picture."

"Have you told this to anyone else?" asked Nancy.

"No," replied Randi. "A good journalist doesn't go around blabbing about her biggest story before she's even written it. So tell me, what are you really really doing here?" doing here?"

"I can't tell you. But I will when it's over," Nancy promised. "As long as you keep quiet about it now."

"Deal," Randi agreed.

Nancy groaned inwardly as she walked away. A reporter on the trail of a hot scoop was the last thing she needed. She just hoped Randi kept her word.

For the next couple of hours Nancy was too busy helping bewildered soph.o.m.ores understand the mysteries of past participles to give any thought to her case. When she ushered her last student out the door, she returned to her desk to do some quiet thinking.

Could she eliminate Randi as a suspect? She was inclined to say yes. Yet one thing still bothered her. Randi had been the only one near the newspaper office when the threatening message was sent.

"Hey, I can practically see the wheels going around!" Victor said, interrupting her thoughts. He was standing in the doorway, grinning at her. "Do you know you have steam coming out of your ears?"

Nancy gave a laugh. "Hi, Victor," she said, in a tone of resignation.

"Wow, what enthusiasm!" he replied, falling into the chair across from her. "You looked a lot more lively when I saw you down in the faculty lounge. Maybe you need to drink more coffee."

"Maybe I need to do less tutoring," retorted Nancy. "By the way, what were you doing in the faculty lounge?"

"Uh-oh, she's starting to pull rank on me," he teased. "I had a right to be there. I was picking up something for one of my teachers."

Nancy sat up straighter. "Oh? What? For whom?"

He opened his eyes wide. "'For whom,'" he repeated. "Golly, if I keep hanging around with you, can I learn to talk like that? Or am I a hopeless case?"

"You're the one who said it, not me," Nancy replied, with mock sternness. "But seriously, how about answering my question?"

"About the package? Sure. Mr. Parley, my physics teacher, ordered some reprints of an article, and he asked me to get them from his mailbox and bring them to the lab for him. Why?"

Victor's story could easily be checked, so easily that Nancy doubted he would have told it if it weren't true. Still, that didn't mean that the reprints were the only thing he had picked up in the mailroom.

"You didn't notice a brown envelope, about this big, did you?" she asked, indicating the size with her hands. "Someone was supposed to leave it for me, but it hasn't turned up."

"Nope," he replied, shaking his head. "But I wasn't really paying attention. I was too busy plotting my next exploit."

Nancy raised an eyebrow. "And what's that?"

"Just imagine," he said, leaning closer. "Tomorrow morning, at the beginning of first period, a cartoon of the headmaster's face appears on the screen of every terminal in the school."

"Victor-" Nancy began.

He held up his hand. "Wait, I'm not done. The eyes look one way, then the other. Then, just when everybody is getting spooked, he puts his thumbs in his ears, wiggles his fingers, sticks out his tongue, and makes a really rude noise!"

Nancy laughed in spite of herself. "You won't really do it, will you?" she asked. "You'd get yourself expelled!"

"I know," he said with a sigh. "I have to face it-I'm chicken."

Nancy sat back and studied him a moment. She couldn't think of anyone who made her laugh as often as Victor did. She was growing to like him and had to admit that she found him very attractive. But if he was guilty, Nancy couldn't afford to be blinded by his charm.

She'd been hoping not to have to wade through stacks of paper records. But now she could see she'd have to do it. Obviously, she couldn't cross-check everyone's records. With four hundred students at Brewster, each taking five courses a year and being graded four times in each course, that would make-eight thousand data points to check. But she could start by cross-checking Victor's and Kim's grades, those of her tutoring students, and then a few other students at random.