Earvin Johnson, Gregory Kelser and their Michigan State Magic Show barnstormed past hapless Pennyslvania today with a devastating display of all around basketball wizardry.

The Spartans started fast and never let up as they buried the outclassed and bewildered Ivy Leaguers, 101-67, to advance to the national collegiate basketball championship final Monday night.

The game was even more lopsided than the score indicated, as Michigan State opened a 50-17 lead at halftime.

Penn looked as if it were suffering from terminal stage fright, and Michigan State went right into its crowdpleasing, wide-open, run-and-gun game.

Johnson, the wondrous 6-foot-8 Michigan State sophomore who will probably turn professional next season, made nine of 10 shots from the field, 11 of 12 from the line and had 10 rebounds, 10 assists and three steals on his way to the 29 points.

Kelser was 12 for 19 and nine rebounds, three assists, blocked four shots and scored 28 points.

The Spartans shot 63 percent from the field.

Most of Penn's problems centered on its inability to put the ball in the basket. The Quakers missed 30 of 36 first-half shots and shot only 29 percent for the game.

The Quakers were getting numerous close-in shots early, but they weren't falling. Penn then started pressing, and after a while, many shots started banging harmlessly off the backboard and others never even drew iron.

Nothing seemed to bother Michigan State, which equaled the most points ever scored in the national semifinals or final. The Spartan's halftime margin was the largest ever in the history of the final four.

"I feel a little bad for Penn," Johnson said, "but they have a good team. They didn't make it here on a humbug, but we don't want any close games if we can help it. We want to beat everybody bad."

Penn did not want to get into a running game with Michigan State, but its only chance of winning was to get an early lead and then try to slow things down. So the Quakers came out running. But after they tied the score, 4-4, the game turned into a nightmare.

Michigan State started rolling and with Johnson scoring from outside and Kelser hitting from everywhere, the Spartans exploded to a 40-8 lead with 3:18 left in the half.

Penn went scoreless in one nine-minute stretch in that span, missing 11 straight shots and turning the ball over six times.

The first half also gave Mighigan State a chance to have fun. Johnson grinned most of the time and the Spartans were playing as if they didn't have a care in the world.

Most scouts say the way to control Johnson is to play off him when he has the ball, force him to shoot, because he is not a good outside shooter, and deny him the passing lanes.

The Quakers played a zone defense most of the game and they dropped off Johnson whenever he had the ball outside the free throw line.

Johnson made four straight baskets from 17 feet and had 14 points and three assists in a 29-2 Michigan State scoring spurt after the 4-4 tie.

"They played off me, so I had to shoot," Johnson said. "If I'm straight up, looking at the basket, I'm going to shoot it and it's going in."

There was a lull in the action with 4:21 left and Michigan State on top, 38-8. Kelser strolled by the press table and asked, "We're doing it to them, aren't we?"

Yes, they were.

Penn played the Spartans even in the second half, but barring a miracle, there was no way the Quakers were going to make up 33 points.

Michigan State Coach Jud Heathcote took Johnson and Kelser out with 5:33 left and the Spartans on top, 88-50.

Tony Price was Penn's leading scorer with 18 points, but Tim Smith, the Quakers' second leading scorer this season with a 13.7 average, went scoreless today and fouled out after playing 19 minutes.

"We were tight at the beginning," Price said. "We've never been here before and I think we got caught up in things."

"Obviously the beginning of the game didn't go like we wanted it to," said Penn Coach Bob Weinhauer. "To be here is a great feeling, but not being competitive doesn't feel too good. Michigan State is certainly riding a hot streak."

The Spartans hav had a relatively easy time in all four of their tournament games. The 12-point victory over Notre Dame in the Mideast Regional final was the closet game they have had.

"We're very pleased, but we are surprised to win so easily," Heathcote said.

"I think they panicked a bit when they got 12 to 15 behind. All we did was keep playing."

"We didn't set out to embarrass Penn, but we didn't want to embarrass ourselves, either." CAPTION: Picture, Terry Donnelly of Michigan State writhes in agony after being submarined by Penn player while making layup.Donnelly returned to game. Penn's Ed Kuhl has ball. AP