The CFI and his student in a C-150 were practicing touch and go's and announcing their intentions on CTAF 122.9, which they had been monitoring. The CFI said he observed no traffic ahead in the pattern and he scanned for traffic throughout the pattern and did not see anything. He said he also announced the turn to base over the CTAF. The CFI stated, 'From this point I transferred my attention between my student and the approach and landing stage of the flight.' He said as we turned final we 'clipped' another ACFT. The CFI stated that he was at the controls at the time of the collision. Witnesses stated that the ACFT C-182 was observed flying upwind against the traffic pattern at an altitude higher than the pattern. The aircraft then crossed the end of RWY 22 and entered a high right downwind, then turned a high long final for RWY 22. At the same time they noticed the C-150 on a left base leg then the collision. The previous CTAF of 122.7 had recently been changed to 122.9 CTAF. The standard traffic pattern for RWY 22 is left hand.