My car shifts hard when accelrating

Band is blown in your transmission or is going. Eventually you will shift into first and then be like your in neutral when the car looks for the next gear. Smell your transmission fluid it will look off colored or smell burned most cases

Check the Coolant (antifreeze) level. My 94 continental has a hard time shifting from 2nd to 3rd when the level is low. Also, this may indicate that the transmission fluid is too old to work properly. The transmission fluid is cooled at the bottom of the radiator, since cool fluid works better than hot fluid (especially when the trans fluid is old) that could make the transmission not shift properly. Keep the coolant level up until you can have the trans fluid checked.

It could be clutch problem, did you check the clutch basket ?
If not, check the gearbox oil level.

Do the brake lights work?

If it was me, the first step would be taking it to a transmission shop for a tranny-fluid change (unless you are a real wrench and can do it yourself). The transmission fluid can get dirty, breakdown from heat and/or general use/abuse, and the filter can become clogged.

the reving high is your idle air control valve ,and it is suppose to do that.have the transmission checked

do you have a leak and the fluid level keeps dropping?low fluid will do a lot of your problems

Have the transmission control module tested.

The possiblities that come to mind are
1 Bad synchro in transmission 2 bad bearing(s) in transmission input shaft.   3 Bent shift linkage or shift fork (I doubt this, but it's possible)
Only number 3 is relatively cheap.  I'd go back to where/who you bought the car from, if it was that way when you bought it, and ask them to help.  It can't hurt.

Using force is NOT the solution.  If the syncros are bad, until you get them replaced, you'll be better off to determine the RPM difference between 2&3 gears (maybe 800-1000?) and also 4&5 gears (maybe 500-800?) and learn to put a modest amount of effort at exactly the time the rpms fall into that diffference.  
Example Say the difference between 2nd gear at 3500 RPM and 3rd gear is 1000 RPM, then when you take it out of 2nd for an upshift to third,  delay until the RPMs are just getting to 2500. If you are on a budget and can't fix the transmission (it's going to be big bucks) you may find you can get pretty good at this.    It is possibly to shift a car this way without even using the clutch, although I don't recommend this and it takes a great deal of practice and luck.
While you have this problem, don't downshift into 3rd,  just run the RPMs down in 4th (say to 2000 or less) until you can shift into 2nd at an acceptable RPM. The least amount of shifting you can do until you resolve this the better.
Another choice until you can fix it, is to just run up the RPMs in 2nd and then shift to 4th, and then forget you have a fifth gear.  This is much better than forcing, it's possible to do more damage by forcing. 
Is it hard to get into 3rd from 4th AND 2nd?  
..ajm

The problem sounds like your kick down cable has gone bad. There should be a cable that runs from the transmission to the linkage on the TBI(i'm assuming it is a TBI[Throttle Body Injection]) At the throttle bracket, it is the lowest cable. It should have a little plastic box and you should be able to push on the button and slide the little plastic piece in or out of the box. This will adjust your shift points, being plastic, the cable likes to slip if it gets old. Also if you have book or have access to one it should tell you how to locate and check it but usually you have to replace them once they start to slip, the one I got for my 1992 was only like 28 dollars so it's not to bad just a real pain.