Cornerstone Academics
Penstone Writing: Grade 3 Writing Lessons App
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One subscription = one student, Grade 3. $7.99 a month per student. For more than one student, set the quantity to the number of students. Each grade is its own product, so this subscription opens the Grade 3 lessons.
Penstone Writing is a complete writing course for Grade 3, taught inside an app. Grades 3 through 5 are where children learn to build a real paragraph: a topic sentence, details in order, and a closing sentence that wraps it up. Penstone teaches that one clear step at a time.
What Grade 3 includes:
- A core path of 8 steps (47 lessons), done in order: Topic Sentences & Closing Sentences, Run-On Sentences, Key Word Notes & Rewrite, Transitions, Story Retelling, Sentence Starters, Style Tools, and Opinion Writing
- 6 optional modules (36 more lessons): Writing from Pictures, Personal Narrative, Book Summary & Response, Poetry, Finishing Touches, and Letter Writing. Many modules also offer optional extra practice
- Teach It: lessons open with a short narrated slideshow that shows the skill step by step. Students can go back, replay, or move on at their own pace, or read the lesson instead
- Key word notes to paragraph: Students read a short, true source and pull three or four key words from each sentence. Then the source is put away, and they write a paragraph from their notes, in their own words.
- A Run-On Sentences module early in the path, so complete, correctly punctuated sentences become a habit
- Checks with real feedback: each writing lesson has 3 key word notes checks and 3 paragraph checks, and skill-practice lessons have 5 checks. The notes check looks at each line of notes; the paragraph check scores the paragraph against a clear rubric and points to the exact sentence to fix
- A writing tutor (AI-powered) that never writes for the student. Students can type or talk to it at any time. It answers with hints and questions, stays on writing, and keeps the work in the student's own words
- Parent Review: everything your student submitted in a lesson, with the tutor's feedback and the rubric, in one printable page. Parents can turn rubric items on or off and change the points
- One family start screen: each child gets their own profile and their own saved work
- Progress syncs automatically across devices
All lessons, sources, and examples are original, warm in tone, and written for families. Best on a laptop or tablet. Talking to the tutor works in Chrome, Edge, and Safari.
Try it free: every grade's first lessons are free to try before you buy: Finding the Topic Sentence, and the first key word notes lesson for Grade 3 (Beavers).
Paper Coach is sold separately. Paper Coach reviews papers your student writes on their own. It is not included here; see Paper Coach.
How access works: After purchase, open My Apps or the Penstone Writing page and log in with the same email you used at checkout. The Grade 3 lessons unlock automatically.
New to Penstone? Take the parent tour to see how a lesson works from start to finish.

What parents and teachers say.
From the teachers, friends, and parents who know Serena's work from the inside.
Amazing! I love writing and want my children to also develope appreciation for it as well, this curriculum will help cultivate that.
It is perfect for the homeschool family who wants excellent writing style without the stress and pressure. The Teacher's guide walks you through each lesson so you can teach with confidence. Ten stars for Cornerstone Academics!
Sarah Samuel Mother of 3
We are so grateful for Serena! Her patience, kindness, and creative approach to teaching have made learning a wonderful experience for our family. She takes the time to understand how each child learns best and tailors every lesson to keep them engaged and excited. We have seen incredible growth not only in our child’s academic progress, but also in his confidence and love for learning. We could not ask for a better teacher!
Bethany Mitchell Mother
Serena is a wonderful teacher who treats every student with kindness, fairness, and respect. She encourages her students to challenge themselves and do their best, and she keeps parents well informed about their child’s progress. We truly appreciate her dedication and support.
PARENT OF A FORMER STUDENT

Read one story. Teach one week. Decide from experience.
Use it with your child. See samples of our stories, questions, and lesson pages.