All science must be taught with integrity and honestly, that's what I ask.
I am not against the teaching of evolution, I am against the teaching of evolution as fact, and not a belief or hypothesis. I'm am against the myriad of dishonest, deceiving scientific "discoveries" in the past century which are meant to coax one into believing a certain observation is scientific fact.
Piltdown Man!
I don't think Piltdown provides a basis for indicting the scientific community (or anthropologists, or evolutionists) generally, since it was an intentional fraud carried out -- most probably -- by a single individual (Charles Dawson).
Among the rest of the scientific community there was a broad range of reaction, from some who probably accepted it too readily (Woodward and G.E. Smith) to, a majority actually, who were highly skeptical.
Skeptical, that is, that the jaw and the skull belonged together as a single individual. No one guessed apparently at the possibility of intentional fraud. Anyway the many skeptics tended to focus on the correct solution, apart at least from recognizing the fraud: i.e. that the skull was human and the jaw belonged to an ape.
In fact, with the leading anthropologists of France and America in dissent, the hoax might even be said to have been failing. Piltdown II (a "find" the hoaxer Dawson engineered just before his death) was crucial to resuscitating Piltdown. One fortuitous association of ape and human materials might be attributed to chance, but not two.
Brief Chronology:
1908 -- Dawson (1908-1911) "discovers" first Piltdown fragments
1912 -- Dawson contacts Woodward in January about first skull fragments and later shows him the site which they begin digging together. In December Piltdown is officially presented.
1915 -- Piltdown II "found" by Dawson
1916 -- Dawson dies.
1917 -- Woodward announces discovery of Piltdown II.
Some of the skeptics were converted by Piltdown II, and others remained skeptical but tended to fall silent.
I've read a great deal of what is available regarding Piltdown, and I can only think of one blameworthy ethical fault apart from the actions of Dawson himself (or whoever the hoaxer was for those that may have a differing opinion): Woodward was intentionally coy about the location of the Piltdown II site. (Which pretty obviously never existed as a "site" in fact, although Woodward didn't know that having been completely taken in by Dawson.)
Anyway Dawson had only given Woodward the approximate location of the (supposed) Piltdown II site. But Woodward, not quite through outright deception, but through artful lack of clarity, allowed most of his colleagues to assume he knew the exact location. In truth he spent years looking for it.
Apart from that everyone so far as I know acted honestly.
But I would guess, like most creationists, you want to specifically belabor the fact that evolution is "only" a theory, but don't want equal, or even comparable, emphasis placed on the fact that photosynthesis (just for instance, among the hundreds of theories invoked, but rarely actually specified as such, in the typical secondary school curricula) is also "only" a theory.