My suggestion is ....

So my idea was to buy healthier sausages and give the students some.

I wanted to see if they say "yes - I will buy some''

If they say "no" then I won't do anything about it and we will still have the same sausages.

The sausages that we eat have about 7gs of fat but we like them. I also  thought healthy sounded yuck!
So.....

I decided that we can still have the same sausages but make the students do exercise after lunch.

.