How would you like to travel around France this summer and deduct the expenses from your income tax? Your friendly, helpful Internal Revenue Service is inviting some lucky taxpayers to do just that.

Looking up from their ledger sheets long enough to note the arrival of summer, the folks in the Baltimore district office of the IRS sent out a reminder that teachers who "travel to maintain or enhance their education skills" while school is out can write off the cost.

Jane Doe, a hypothetical French teacher, is planning to spend her summer in France, "visiting schools and families, attending movies, plays and lectures in the French language," the IRS notice says. She can deduct the cost of meals and lodging and the cost of tuition, books and lab fees for any courses she takes.

Of course, this offer isn't open to everybody. The travel has to be directly related to the teacher's work. "Teachers of English or math cannot deduct the cost of a similar trip," the IRS said. The notice did not say where a math teacher might go that would be directly related to his or her job, but it said that, in general, travel costs are deductible if the "major part of the activities during the travel directly maintains or improves" the teacher's skills.

A recent communication from Michael Murphy, the IRS district director in Atlanta, was a lot less convivial in tone.

Murphy's office released the text of a letter he wrote to a taxpayer who invested in a tax-shelter promotion that the IRS considers "abusive" and therefore not deductible under the 1982 tax law, warning him that he'd get hit with penalities if he tried to claim it on his next return.

Usually the IRS waits until a return is filed before challenging a deduction, but associate commissioner Philip E. Coates recently told Congress that the agency is planning to use more of these preemptive strikes in an effort to discourage the promoters of fraudulent taxpayers by frightening away investors.

Murphy's letter said the IRS had "information" that the taxpayer had invested in a particular tax shelter. "Based upon our review of that promotion, we have determined that the purported tax deductions are not allowable. If you claim such deductions on your income tax return, your return will be examined and the deductions disallowed," the letter continued, and the taxpayer faces negligence and overvaluation penalties if he tries to claim them.

The IRS wants Congress to require that tax-shelter promoters give the IRS the names of everyone who invests in them, so that this kind of advance warning can be sent to all investors.

Without such a requirement, Coates said, investors can't be headed off in advance, and once the shelter is operating there is no way of telling how many taxpayers are participating in it. If the names are registered, discovery of a questionable shelter during an audit of one taxpayer would enable the IRS to scrutinize the returns of all others participating in the same scheme.

Coates, who was representing the IRS while commissioner Roscoe L. Egger Jr. recuperated from surgery, said some tax-shelter promoters have been "openly breaking the law" by packaging phony investments such as nonexistent gold mines. In 1982, he said, the IRS criminal division recommended prosecuting 102 promoters of allegedly fraudulent shelters that had signed up 13,000 investors.

Since the beginning of 1982, he said, 29 of these promoters have been sentenced to jail.