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70 thoughts on “Contact Us

  1. I am at a crossroads with choosing a geometry curriculum for my 9th grader. We started out using a curriculum that is really just not working for him, and since we’re nearing the end of the first semester, I really want to get it right when we switch. I’m not so worried about timing, more about the frustration of something not working. We have never used Saxon before and so I’m not acquainted with the style, but have heard mixed reviews about both Saxon and Jacobs. Can you please give my some insight about these two? Thank you.

    1. Kaylin – Thanks for the question – I know we talked over email about this. Hope you have a solid plan for your family now.

  2. I already own the older version of the Elementary Algebra book (the one with the geckos on the cover) and the associated Solutions Manual. Will these work with your DVD/online videos and Teacher’s Guide?

    1. Yes, these will work just fine. That was the textbook version we originally used to create the video content.

  3. Do I need to order the textbooks for geometry, if I purchase the online geometry curriculum? Is your curriculum self directed, so that my son can work independently? Will quizzes/ tests be done online, or would I, as the parent, have to administer them? Can the geometry class be completed in a semester? If so, is there a schedule to help accomplish this time-frame? My son has just completed Saxon algebra 1 3rd edition. Will that make a difference for your geometry curriculum? If he takes your geometry class and decides to take your algebra 2 + trig course, how much time is required to complete these courses? The reason we are looking at your curriculum, opposed to doing Saxon algebra 2 (with the other half of geometry) is because my son is behind in math, since he started his 9th grade late fall and had to take pre-algebra (instead of algebra 1) due to severe illness. With him being in 11th grade and needing to take his SAT this spring, we are concerned. In summary, please let me know how much time it would take to complete geometry and algebra 2 + trig, is geometry required for higher level math, and if the courses can all be completed online (my son’s preference) independently? Thank you in advance for your time and assistance.

    1. The online course does require the textbook, solutions manual, and teacher’s guide. The online material is teaching the textbook content. Many students/parents do this independently. The tests are not online but are contained in the teacher’s guide. For most parents, the student does everything alone except for grading the tests. However, some parents even have the students do their own grading. In terms of time, yes it can be done in a semester. In a college setting both the geometry and the Algebra 2 with Trig would be done in a semester. Just take the timeline provided in the teacher’s guide and do the work faster. We provide an online PDF version of the teacher’s guide which has the student working fewer problems that would help. If you have other questions, the fastest way to get a response is at

  4. Is there a DVD available to shows how problems are worked out step by step? I have purchased the online version of Dr. Callahan’s Geometry. But, I am really nervous about my student doing geometry this coming fall especially given the fact that I will be of little help to her.

    Do you have any further suggestions for seeking out help for the struggling geometry student?

    1. The online version is the best option. The DVDs are the same content – but unlike the DVDs, we do change the online version to meet needs and add answers to common questions. No need to be nervous – we will be there to help you. Inside the online course, there is a way to get help which might be how to work on a problem or seeing if your work was correct even if the answer is a little different than the book.

  5. I tried to complete an order but it says i have no shipping options for my address…. I’m not sure what to do … its a normal address… but no matter what I do it won’t let me purchase the math.

    1. We have been having some issues and are working on it. We will send you an email direct to work this out.

  6. Hello, We just completed Saxon Algebra 2.
    What do you recommend next from your company for a Senior Home educated student? She is looking into Forensic Science and Law Enforcement programs. Thank you.

    1. To help you think through what math options you have – check this out But since her path may not need any more traditional math – you might instead consider something that pushes her forward to where she wants to be. For that, I would suggest doing College and Career Planning. This course will help her do things that will give her a head start on her path and help her move to connect with professionals in her desired field. See

  7. Homeschool mom trying to sort out what I need for geometry next year.
    1. is the streaming instruction the exact same content as what is on the DVDs?
    2. If I have an older version of the 3rd edition, specifically the one with the the chess pieces, will it still correspond correctly to the DVD content?
    3. where are the tests? I don’t see a separate test book. Are they in the text? Where are the answers for the tests?
    4. Do I need both the solutions manual and teacher book if we are using instructional DVD?

    1. 1. Yes the streaming and the DVD both contain the same content.
      2. All 3rd edition textbooks work with the videos. The only changes from yours might be 1) page number references and 2) problem references since the newer version has different page numbers and some problems changed. These are pretty minor.
      3. Tests are found in the Teacher’s Guide.
      4. Yes, we would highly recommend both.

  8. My son just finished his Jacob’s Geometry last week. It auto-renewed today (on a holiday weekend), is it possible to receive a refund? I didn’t want to cancel before his final exam, just in case the subscription stopped immediately. Thank you.

    1. Will send you email directly.

  9. Are your instructional videos only watched via the internet or can if we order the “everything” option for Algebra 2 w/Trig does it or can it come with DVDs vs online access? Our internet is sketchy and I am trying to get away from my children having to be online and have internet access. Thank you!

    1. We will email you directly to see if we can find a solution to help you.

  10. When my oldest son started Algebra 1, there was a suggested schedule we found on your website (I think!) with the recommended problems to complete. Is there such a schedule for Algebra 2 with Trig?

  11. hello, I purchased the Geometry online course, but have not received a email related to log in, how do I access the videos? thank you.

    1. So sorry – we made a change to the system and it dropped the automatic login details coming. Thanks for pointing this out. Your login details should be coming to you in a few minutes.

      1. I received the email, but cannot access the videos, the website will not except the password I received. I pushed the forgot password button, but still could not change it, because the website it took me to was not allowing me to change it. what do I do to access the videos?

        1. Are you sure you are going to the correct site? Should be

          Will send you more information in and email

  12. Are there alternate tests available for Alg2 w/Trig. After the first 2 tests we are considering “starting over” to make sure we have the concepts down. Or what would you suggest?

    1. We only have the ones in the Teacher’s Guide. As alternatives, you could pick some chapter 2 review exercises (see page 165). Try chapter 2 review #s 3,7,15,21,33,67 and chapter 3 review #s 9, 11,19,22 (since answer not on the book check by graphing on calculator or, 27,45, 71.

  13. What is the difference between the teacher manuals for Elementary Algebra by Harold Jacobs & the one by Ask Dr. Callahan? Am I missing anything by getting one over the other? Or is there a benefit to using one over the other?

    1. If you are buying the new book (blue cover with the world on it) you need to get the Teachers Guide that matches. Both are published by Master Books. The Master Books teachers guide contains the set 3 problems of the book and is a critical part of the book. We no longer offer a printed copy of the Teacher’s Guide by AskDrCallahan – it is downloaded only. The only advantage to downloading our teacher’s guide is that we use a different syllabus and we do not assign every problem.

  14. have an older version of the Algebra text book (with the geckos on the cover). I was going to buy the older version of the solutions manual. Is this newer version the same thing? Are there differences?


    1. Your best bet is to find the solutions manual that has the same/similar cover. While technically they are all the same version, the printings differ and you will find some differences in the problems sets. But if you cannot find one that matches – yes go ahead and get the newer one and then just make adjustments. The problems that did change are often documented on our support page.

  15. I need to speak to someone about a possible reimbursement. I purchased the Algebra 2 with Trig yesterday for my son, but it appears my wife had already ordered something before she passed away last Wednesday. Can someone contact me about my issue?

    1. Will replay via email directly.

  16. Good morning, I’m wondering if the current textbook printing for elementary algebra (blue with the world image) will work fine with using the DVDs from the previous cover design (burgundy/numbers) Are the any discrepancies between the 2 covers/editions? Or are the changes merely an updated cover? If the content has changed, I would assume that it is recommended that the new text be used in conjunction with the corresponding current DVD set. Thanks in advance for your reply.

    1. Yes, the DVDs and online videos still work with that textbook. The new textbook is mostly a repackaging with a new cover and some image changes.

  17. My son did Videotext for all of his Algebra 1 (8th grade) and Algebra 2 (9th grade). He began their Geometry program in 10th grade, but we did not like it so we switched to Harold Jacobs Geometry half way through the year. After completing the Geometry during his 11th grade year, my son did the Trigonometry chapters in the College Algebra 2 and Trigonometry book. You mention that the College Algebra 2 and Trigonometry course is just like a Pre-Calculus course. Am I able to give my son a credit in Precalculus for completing the Trig that was covered in the Trig course you offer and the part that was covered in Videotext? If not what more do I need to have him complete so that he is able to have a Pre-calculus credit?
    Thank you!

    1. Yes I would in terms of a transcript. Now the question is his next steps. If he is heading to college and looking at some STEM field, you might want to make sure he has the math down strong – no matter what you call it. I would move on to Calculus which should be an indicator. If he is not heading into a STEM field you do not have to worry quite as much about it. My reasoning is that we lose most students in STEM because of math – and many come from a solid math background. MAny of the homeschool math programs do not adequately prepare students for college-level math.

  18. I have the 2000 printing of the Jacob’s Text (original). Will the revised solutions manual correspond with the older text? Or do I have to purchase a new textbook to use the solutions manual? Thank you.

    1. There will be some differences since some of the problems were reworded. So the best bet would be to find the old solutions manual. Find a used copy here

  19. If I buy the online algebra, I am assuming I still need to also buy the textbook, solutions manual, and teachers manual, correct?
    Thank you

    1. That is correct. The videos (on either DVD or streaming) are just the teaching.

  20. I learned about Jacobs’ Math Textbooks while searching for the next steps for my 11 year old completing Singapore Primary Math US 6b. It seems that some families are using these books starting in 7th grade, but that they are presented as high school or even college-level text books. I was wondering whether you’d be able to give your view on the subject. Would you support the view that, in most cases, older students (typical high school age) would be more developmentally ready this coursework? If so, would you have recommendations that would help prepare students during this intermediate phase? Would “Mathematics, A Human Endeavor” be appropriate? Are there any Pre-Algebra courses you’d recommend? Or, would taking on Elementary Algebra with a two-year pacing be appropriate? Thanks so much for your advice!

    1. Mendy,

      My default is to take Algebra and taking your time through it is the best approach. Some take 2 years, others go faster. Technically Jacobs Algebra and Geometry is not college level (even though we see some colleges using it) – but certainly college prep. Our other two courses – Algebra 2 with Trig and Calculus – are 10% college level.

      Here are options in the order we would try them:
      1. Geth e Jacobs Algebra and try it for a while and see how it works. If you find areas that your student is not ready for, go to Math Mammoth and download the appropriate sheets to help fill that void. Then go back to Algebra and repeat. This is how we did out older son.

      2. Use Math Mammoth for their prealgebra. No videos by easy enough to do.

      3. Use Life of Fred at the prealgebra or algebra level as a slow intro.

      I give these three because students are all different and like different things. You might even stick with Singapore if they have an algebra/prealgebra option.

      Where the breakdown comes for college prep is after Geometry. If your student is heading for anything math intensive in college (science, engineering, or even business now) they will be best served by getting into college prep material earlier. A lot of homeschool material at the Algebra 2 and above level is really watered down.

      Hope this helps.

  21. Do you sell the Teacher’s Guide for Jacob’s Geometry as shown in the bundle picture on your site? I don’t see it in the individual list of prices.

    1. Sorry for the delay – got caught in spam filters. Yes we do. Here is the link.

  22. We purchased the Jacobs Geometry (3rd edition) two years ago and are beginning it with our daughter this year. I ran into trouble grading her very first test, as her answers on problems 18 and 19 were both off by just one degree. I’ve searched in the teacher book and online to no avail to figure out if this is acceptable or not. Should she receive partial credit for answers that are off by such a small amount or does the entire problem get marked wrong?

    Thanks for your reply!

    1. No need to worry about being off 1 degree on a physical measurement (using a protractor and paper). I would give full credit.

  23. Hi, I placed an order an order for the online algebra 2 and trig course yesterday, and I have nit yet received the log in details.

    1. They were sent immediately after your order. The email might have gotten caught in a spam filter. We will email you again just in case.

  24. Hi, this is Melanie from Math n Stuff in Seattle, WA. We are wondering if you would please send us a current product and price list, as the one we have is from 2015. Please either snail mail it to us at:

    Math n Stuff
    c/o Gini Wingard-Phillips
    8926 Roosevelt Way NE
    Seattle, WA 98115-3043

    or email it to us at the address below.

    Thank you!!

    1. Melanie,

      We sent you an email with our current distributor’s agreement.

  25. I accidentally ordered 2 sets of Algebra 2 with Trig. Can I mail the extra set back and get a refund for that set?

  26. I ordered the Algebra II bundle. The order number is 4144. placed the order on 8/29/18. When can expect to receive it?


    1. Renee – We are that it delivered on 9/1. We had emailed to confirm shipping contents and were waiting on a reply but went ahead and shipped on 8/31.

  27. We had a great experience with Geometry for the past 10 months. We no longer need geometry and we are trying to cancel our monthly subscription. There is no way of doing so on your website. Please let us know how we can cancel at your earliest convenience. Thank you, Yvette Carrillo

    1. Yvette, You should be able to do that if you log in to your account on the sales site (this site). However, we went ahead and canceled for you. We will follow up with an email to confirm.

  28. Dr. Callahan,

    I purchased the Algebra – Everything You Need package for $230 on Feb. 13, 2018 from your website. I am unsure which syllabus my son should use for this upcoming academic year. Should he follow the weekly schedule included in the “Elementary Algebra Teacher Guide,” which appears to be a newer edition, or the syllabus I printed from the Teacher’s Guide on the AskDrCallahan CD-ROM?

    Thank you for your assistance,

    1. Corina,

      I would go ahead and follow the one in the new book – just to be complete. However, you might want to look at the reduced number of problems we suggest using if working all of the problems begins to be an overwhelming amount of time.


  29. Hello:
    I purchased your monthly subscription for the Algebra 1 videos. I received the login info via email as well as the link to access the course. When I click on the Algebra 1 link, I receive a message indicating that I do not have access and that I need to log in. When I click the log in link. It takes me to a wordpress log in page. It will not accept my username or password. I need help. As it stands now, I cannot gain access to the videos in my subscription.

    1. Sorry to hear that. Looks like you did not get your login information via email. We have resent – please check your email for details.

  30. I am trying to decide between ordering the online course or the DVDs for algebra and geometry for my two children. I think the online course would be more convenient for watching. Can my children go back and rewatch any previous lessons on the online course? Thank you.

    1. Yes they are the same. And yes, you can go forward or back as much as you need in the course. There is a setting online where you can mark the content as complete – but that is just for your tracking and does not stop you from going back

  31. Dr. Callahan,
    1) Does the solutions manual contain solely the answer to daily problems and test questions, or does it have an example of how the problem is worked out for the student to see should they have a question. If a student has a question regarding problem solving , how accessible is support for immediate feedback if examples are not provided in solutions manual.
    2) What is the difference between the Geometry book with the Bee on the cover, and the one pictured in the Geometry bundle on your web site. Does the On line Course correspond with both books?

    1. 1) The solutions manual contains the answer as well as the steps needed to get to the answer. The amount of detail varies based on the complexity of the problem. It does not contain examples of other problems. Our support via email is done usually within 24 hours – often less. It is the fastest way to get a response. Even questions like this can be addressed at

      2) The one with the bee on the cover is the latest printing (not edition). This is the one we, and almost every vendor, now carry. ANy 3rd edition (there have been 3 printings with 3 different covers) work with our videos.


    1. Sorry, we were a little late. If you have any other questions – please let us know.

  33. I am interested in the geometry curriculum. I first found you in the DVD set offered by Master books. That DVD says it is only 4 hours long for the whole book. That seems really short to me to cover everything. Then I found you have your own site and your geometry DVDs show 2 in the set and it is 12 hours. That seems much more like it would cover the whole book. I was wondering if the Master Books DVD really is only 4 hours how that could possibly be enough information for the whole book and if your set really will cover all the material so that it would be like a video for each lesson. Thank you for your help in this matter. I just want to know what to expect if I choose to use the DVDs with the textbook.

    1. They are both the same content. The 12 hours is a misprint (we will fix) but might also be longer than 4 hours – again we will check. But do not get caught up in the hours – this is not a classroom where the students have to listen for an hour at a time. Most of our videos are less than 15 minutes. Math is a skill – like the piano. You cannot learn it by listening to others talk – you have to do it and apply it.

      Here is how the teaching works. First, we cover the concept of the section or sections. Then we look at some examples. From that point, we hope to get the students working. If they have problems, they can email us. However, we rarely hear from students taking this course. And when we do, it is often a confusion in what the book is asking for a selected problem. Many students have been through this course with no issue.

  34. I purchased the Algebra I DVD set this evening after I saw your Facebook post regarding the 25% discount on bundles and DVD sets. It stated the LETSDOTHIS code also offered free shipping. When I paid for the DVD set, I was charged for shipping. Did I misunderstand the post? I am content with the 25% discount, but if you offer free shipping as well, I would be glad to receive it. : ) Thank you so much! Amanda Feavel

    April 29, 2016

    1. Yes we saw that and you should have been refunded the shipping cost. Sorry about the trouble.

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