Texas Instruments (TI) are our calculators of choice. There are many other great companies – so this is a personal preference.

Algebra, Geometry, Biology, Chemistry – For these courses, the TI-30 Scientific Calculator is perfect. It is inexpensive and does all you need.

Algebra 2 with Trig, Calculus, Physics, Statistics, and beyond – These courses require a bit more horsepower as well as some graphical tools. Our choice is the TI-84 Plus CE.

Note: The TI-84 Plus CE is approved for use on the following exams: PSAT, SAT, and ACT college entrance exams and AP Exams that allow or require a graphing calculator.

Web Base Calculators

Scientists and engineers are using more powerful tools today. One such tool that is free to use is Wolfram Alpha. It has APPS and extensions for web browsers etc. If you ask us a question on support, this is the tool we use. But, you cannot take it into the ACT/SAT or other tests – so you need to be able to use your calculator also.

Emulators

Emulators are software programs that operate like the calculator. For the TI graphing calculators you can find some here. You may find others by searching You can also find some apps for these and even so a search “TI Emulators”

I have the textbooks and solutions manuals for Algebra I, Geometry, Algebra II and Trigonometry, and Calculus. I no longer need them and am exploring options to sell them. Do you buy textbooks? Thank you all so much for your ministry. It was a huge blessing to me and my brother as we tackled these subjects pretty much by ourselves.

Answer from Dr. Callahan:

We do buy them, but at deep discounts. You might be better off on Ebay or Amazon.

Greetings! I want to begin first to thank you for your excellent math curriculum! My son and husband just completed a successful home-schooling year with your DVD Algebra math program.

For this year, we ordered from Veritas your Geometry DVD program for Geometry: Seeing, Doing and Understanding. Besides the DVD and textbook, we also have the Enhanced Teacher’s Guide and the Test Bank. Do we have all that we need for the Geometry program? Last year, we ordered book containing all of the solutions for the Algebra problems. Are all of the solutions for the Geometry problems found in the materials we already have, or is there a book that we could order separately that contains all of the solutions? Thank you for your help!

Answer from Cassidy Cash:

You have almost everything you need! You will need to add a drawing kit – compass and protractor. You can purchase the kit at most any store that carries school or office supplies. You can also purchase from us at http://www.askdrcallahan.com/products/8-Piece-Geometry-Set.html

One quick note: We do not sell the tests that come with the textbank, but we will help you with them if you choose to use them throughout the course. We wrote our own test for the course, and they come inside the AskDrCallahan Geometry Teachers Guide. That is different from the Enhanced Teachers Guide.

The Enhanced Teachers Guide was written by the same publisher as the textbook, and is essentially the solutions manual, —and YES it does contain solutions to every problem.

If you are wanting to follow the AskDrCallahan program for the course, you will need to use our Teachers Guide. That document comes in pdf form on the first disk of the DVD set you have already purchased, so if you are ok printing your own, there is no need to purchase anything else, I just wanted to be sure you knew that distinction. (we sell hard copies of the Teachers Guide as well if you ever decide you want that, but there is no difference between what we mail you and what you print yourself from the DVDs, so it really about what format you want).

I am so glad you are enjoying our programs! Please let us know if we can help you with anything as you move through Geometry.

We are wrapping up Alg. 1 and are ready to open up Geometry w/ Ask Dr. Callahan DVDs. We are, um, a bit behind schedule and I am wondering if this is a text that must be completed to the end or if there is a good chapter cut-off where we can call it good. (For example, are the last chapters for AP students?) Thanks! The Mom

Answer from Dr. Callahan:

Our Geometry syllabus is setup for one year, but many do complete in one semester. But the wonderful thing about homeschool is that you get to pace as you need.

In the syllabus we do skip some sections that are not needed for the ACT and other courses. I would just ploy into the course since you will realize there is not as much material here as it might seem at first glance. If it does take you longer than one semester – just carry it through. At least – that is what we would do in our home:)

I ordered the Geometry DVD bundle from Lamp Post Homeschool Store last summer to use with my 10th grade daughter. Unfortunately, I seem to have misplaced the syllabus that came with the package that told what homework problems to do per chapter. Is there a syllabus available online or is there any way you can email me the syllabus. Thank you so much for any help you can give me!!

Answer from Lea:

The syllabus is in the Teacher’s Guide. There are a couple of options that will get you to that info. Here they are:

I bought the full Geometry DVD program, It reads on the receipt that there would be a download area on the website, I do not see that, I wanted to see if there have been any changes to the teacher’s key, and I need to download the syllabus. Thanks

Answer from Lea:

The syllabus is in the Teacher’s Guide. There are a couple of options that will get you to that info. Here they are:

My son is using your Geometry course and is doing very well. Geometry seems to be an easier subject for him than Algebra was. I want to use the next course, Algebra 2 with Trig, but I am concerned because he had a difficult time with Algebra 1 (even with the dvd’s). What do you suggest?

Answer from Dr. Callahan:

Put extra focus on those algebra reviews in the geometry book. If he struggles with some of them, take time to review the subject. He is getting more algebra than you think doing geometry anyway – but that review should help lock it in. I might have him go back and do a final test (again) in algebra when he completes geometry to see if he is still weak in areas. It would be worth it spending time reviewing algebra again after geometry if he has not gotten it yet. When done – let us know how it looks and we can suggest some specifics.

I am considering your Geometry program for our children. However I am not convinced yet that I could grade geometric proofs fairly, consistently and accurately. Since proofs have mutiple possible correct answers depending on how the student writes them how do you recommend grading them? And do you provide any help with that or direction in that regard for parents? While I did well in Geometry myself ‘way back’ in the day I am by no means a mathametician either. And I want to be fair to my children. I know you say your program is not ‘proof intensive.’ But since Jacobs covers proof I would think you do as well, correct?

Thanks for any input you can provide regarding correctly handling and grading geometric proofs.

Answer from Dr. Callahan:

The way the text handles proofs is quite different. Instead of long proofs, they tend to be broken into stages of a though f (or however long they need to be).

The result is that there is not as much confusion as you might expect.

So here is how we grade.

– Each problem on the test comes straight out of the book
– The solutions manual is used to grade the tests.
– Each problem is graded either right or wrong – not partial credit.
– Any problem missed is reworked by the student for some partial credit back.

The reason for this method — you learn from your mistakes. Second benefit is that grading is easier.

So, if there is that one problem that they got different from the book, then the rework is a time to look at it. If it applies, full credit should be given.

At times we get parents who ask about these problems to our support line at support@askdrcallahan.com. But there is very few of those.

So for you it might show up 2-3 times per the course – so very doable.

In Harold Jacobs Geometry we skipped over material is chapters 12, 13, 15, and 16 because

1. It is not needed for ACT/SAT nor future math classes, and

2. it is a overly complex for the course at this level.

Our recommendation is that the student look over this material and get the idea – but move on. You will find a test problem that points back to some of this material in a trivial way, but we decided to leave it in as a learning tool since often in life we find ourselves having to dig a little to get to an answer – even when being tested. Since we recommend open book tests, this usually works well. And, just in case, it is only one problem and the teacher can decide to skip it if they like.

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