Palestinian leaders have charged Israeli security forces with applying collective punishment techniques to West Bank's Palestinians protesting Israeli's invasion of southern Lebanon.

An Israeli Defense Ministry spokesman yesterday denied the charges, declaring, "We are not using collective punishment."

But in 10 days since the invasion, Palestinians charged, Israeli security forces have imposed a $62,000 collective fine on Gaza Strip Palestinians, broken school windows in Ramallah and threatened that West Bank town with cuts in water, electricity and food supplies if disturbances continue.

Demonstrations have apparently been directed as much against the impotence of Arab governments as against Israeli's invasion itself, and have take place in East Jerusalem, Nablus, Ramallah, El Bireh, Jericho, Bethlehem and Gaza, as well as some usually quieter smaller villages.

The demonstrators have been more restrained than in the past, however.

One independent observer of West Bank affairs, comparing the incidents to the much more violent rioting that cost dozens of Palestinian lives in the spring of 1976, said: "If 1976 was six on a Richer scale of violence, this was more like two."

The only known deaths according to Israeli spokesmen, were of two Palestinian boys who were killed when an Israeli Army driver lost control of his truck when stoned in Nablus and a Palestinian in Gaza killed trying to take a rifle from an Israeli soldier.

But the reported response to the demonstrations raises questions about Israeli's deteriorating relations with West Bank's residents, long considered the most moderate Palestinians.

About 100 Palestinians have been arrested, and so far military tribunals have fined at least four teenagers as much as $600. Failure to pay automatically leads to a year's imprisonment.

The most prominent West Banker arrested was Raymond Tawil, 39, an outspoken Palestinian nationalist who occasionally contributes to the French-language media.

Tawil, who in 1976 was under house arrest for four months, was arrested at 1 a.m. Thursday at her Ramallah home.Israeli spokesmen said she was being held for questioning regarding alleged terrorist activities and the disorders.

In this Christian village south of Jerusalem, eight boys aged 12 to 14 were reported hospitalized with broken legs Tuesday after jumping 25 feet from a second-story classroom that their headmaster said had been filled with antiriot gas by Israeli troops.

Observers were struck by the apparently uneven handling of various incidents within a few miles and days of each other.

At Bethlehem University Monday, Israeli security forces demonstrated restraint in the face of provocation when Palestinian students stoned them. Instead of entering the campus, the troops used antiriot gas to force students to leave.

Here, at the Iskandar el Khoury school, fewer than half of 560 students, aged 6 to 16, were present yesterday and the headmaster, Louis Abed Rabo, said "the others are afraid" after security forces allegedly launched gas canisters into the school.

The headmaster showed visitors scorch marks left on the stoned floors by what was said to be American CS antiriot gas.

"A soldier opened the door and said 'don't be afraid.' We did not know what was happening, but suddenly we seemed to choke and I jumped out of the window," said Walid Naim Qasir, 14, at the hospital where he is being treated for fractures of both legs.

The headmaster denied that his students provoked the Israelis, and added that about a dozen older youths were sent home because of unruliness. The mayor of Beit Jala, Bishara Daoud, said he personally lectured the students to avoid provocations because he and some other local officials are themselves on trial because of an earlier incident.

"The Israelis are planting hatred," the mayor said. "We have asked the United Nations to protect us . . . and we telegraphed the defense minister (Ezer Wiseman) to investigate."

Asked about this and another similar incident reported by Palestinians, an Israeli Defense Ministry spokesman said security forces has shot CS-gas canisters into both schools in the face of "very severe rioting" involving students throwing stones at passersby.

He said the troops showed "great restraint" and denied that they had entered the school grounds. The spokesman provided no explanation for the scorch marks seen in the classrooms, however.

Symptomatic of West Bank reaction to the Israeli occupaton was the comment of a Western-educated Palestinian upon reading a newspaper advertisement calling for testimony before a U.N. human rights committee.

"Who would dare write, and if anyone went to Geneva to testify, how would he get back into the country?" he asked.