Don't be surprised if much of your first lesson is spent on the ground. As mentioned above, horse can be an unpredictable animal and a good instructor will spend time teaching you about the correct handling of horses, before allowing you to get on. You'll learn about haltering and leading, grooming and tacking up etc. Some people might think this is a waste of money - they are eager to get mounted and get riding. However, this is all part of horsemanship and the more competent you are around horses, the better relationship you will have with them going forward.
Your early lessons will be geared towards giving you the skills you need to become a good rider. You'll learn the correct way to mount, the correct position, the aids which you will use to communicate with the horse, etc.
Many instructors like to give early lessons on the lunge. This is where the horse circles around the instructor on an extra long lead line, called a lunging rein, or longing rein. This gives the instructor control of the horse and allows you, the rider, to concentrate on learning about balance and co-ordination without having to worry about controlling the horse. The lunge-rein is especially helpful when you're trotting for the first time. Sometimes horseback riding can seem very complicated and it's much easier if you only have to think about one thing at a time, until it all becomes second nature.
Your lesson program will be progressive, with each lesson building on skills learned in previous lessons. A good instructor will challenge you, without pressuring you or getting you doing something you're not ready for. At any time during your lessons you should feel comfortable telling your instructor if you think she's moving too fast for you.
Resources:
WWW.BLACKCREEKEQUESTRIAN.CA
WWW.KIDSCAMPS.COM
WWW.LONGACRES.COM
WWW.EHOW.COM
WWW.MYRTLEBEACHHORSEBACKRIDING.COM