We just started it with my almost 8 year old son who also is not a fan of writing, and I haven't found it to be too much. Carrie does a good job spreading it throughout the week. I agree, it might be good to start half-speed for a few weeks or months, though. Also, my son has needed a lot of encouragement for the writing assignments. Like our first history assignment--drawing a labeling a map--I sat next to him the whole time, let him abbreviate a few words (like Is. for island)...made my own map so he could see that it doesn't have to be perfect (and to give him a model to look at) We also took a break half way through. He did fine with it and was very proud of the finished result! Copying the Bible verse I also let him do in parts...and you might use a notebook instead of an index card--it's hard to write that small for some kids.
As for cursive, we started that a few weeks before starting Bigger and he likes it so much better than manuscript! Says it's easier...so you might give it a try. But, if your son isn't ready, Carrie gives the option for poetry copywork instead to be done in manuscript.
We also do English orally (unless there's not much writing that day, in which case I have him do 1-2 sentences written)...and we do a lot of math orally too, as needed. My goal is to slowly work him toward more writing endurance as the year progresses.
All that being said, it is a lot more writing than Beyond (and we enjoyed Beyond a lot too). Beyond could be a nice transition for him--and it'd be easy to beef up the science with library books, nature walks, etc. Have you looked at the first week of Bigger--that might help you decide.
http://www.heartofdakota.com/pdf/BHFHG-first-week.pdf
Also, this is a post about the writing in Bigger, from Julie, which could also help.
Bible - Once per week copy the memory verse
History - Timeline entries once per week (name, dates, and small picture)
Once per week notebooking page that may be a map drawing, list of facts about a person or event, pictures to go with it...
1-3 Vocabulary cards per week (definition, sentence using word, and illustration on the back)
Science - Once per week notebooking page including Bible verse and a labeled drawing
Once per week experiment page (Parent writes question on it, child records a guess, draws the procedure, and writes a conclusion)
Dictation - Study and write short passage 3 times a week (2 sentences)
DITHOR - 2 (?) student pages per week (The teacher guide actually reccommends writing these for your child if writing is an issue starting out.)
Cheerful Cursive - if you're opting to do that (The lessons are very short! I have my child write the words once, even though it says twice on some of the pages, as long as it's GOOD writing.)
R&S2 - Usually about 5 sentences a day (on a white board)
Poetry - OPTIONAL to copy from the poem of the week. We started out without it, and have added in copying 2 lines 4 days a week.
These are spread throughout the week in the plans so that there's not too much on any one day. Cursive and R&S are daily, but the "big" ones are split up.
Day 2 - Science notebooking
Day 3 - vocabulary and science experiment page
Day 4 - Bible verse
Day 5 - History timeline entry and notebooking
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