Suffix Spelling Detectives

Overview

Students investigate how word spellings can change when suffixes are added. They will identify base words, notice vowel and consonant changes, and apply these patterns when spelling and editing Year 8 writing.

Learning intentions

• WALT identify spelling changes when suffixes are added.
• WALT spell words accurately when vowels or consonants change.
• WALT recognise that some spelling patterns are ambiguous and need to be remembered.
• WALT use spelling strategies when editing our own writing.

Success criteria

• I can identify the base word and suffix in a longer word.
• I can explain what has changed in the spelling.
• I can spell at least eight target words accurately.
• I can use a strategy to check an unfamiliar spelling.

Curriculum links

• English — Writing: spelling words where the consonant changes when a suffix is added.
• English — Writing: spelling words where the vowel changes when a suffix is added.
• English — Writing: recognising that some spelling patterns are ambiguous.
• English — Writing: using spelling knowledge and proofreading practices in written work.

Lesson structure (40 minutes)

1. 0–5 min · Hook and notice. Open with the spelling detective hook and display: explain → explanation, mischief → mischievous, happy → happiness. Ask, “Why can’t we always just add the ending?” Students work with a partner to circle the letters that change and share one observation.

2. 5–12 min · Explicit teaching. Use the pattern teaching slides to model three useful patterns:

• A vowel may change: explain → explanation, pronounce → pronunciation, sign → signal.
• A consonant may change or be replaced: mischief → mischievous, magic → magician, critic → criticism.
• Some patterns are ambiguous and must be learned through word families, memory, and checking: nature → natural, electric → electricity.

Emphasise that these are helpful patterns, not rules that work every time. Students repeat each word, identify the base word, and record one example.

3. 12–17 min · Guided word sorting. Display the word pairs from the sorting activity slides. In groups of three, students sort them into “vowel change”, “consonant change”, or “little/no change”: celebrate → celebration, decide → decision, refer → reference, danger → dangerous, comfort → comfortable, care → careful. Groups justify one decision, using the sentence stem: “The spelling changes because…”

4. 17–29 min · Individual practice. Distribute the suffix spelling practice sheet. Students complete the tasks independently, then compare answers with a partner. They underline the base word, add the suffix, and write a short sentence using selected words. Circulate and prompt students to say the word, look for its word family, and check the whole word rather than relying only on sound.

5. 29–35 min · Editing application. Return to the editing challenge slides and show this sentence: “The magician explained the natural changes in electricity.” Provide three deliberately misspelled alternatives on the worksheet or board, such as magicion, naturial, and electricity. Students act as editors: correct the spellings and explain which strategy helped. Invite two students to model checking aloud.

6. 35–40 min · Review and exit check. Use the plenary slides for a rapid review. Students complete the final section of the suffix spelling practice sheet: transform permit into permission, transform music into musician, and write one strategy for checking a difficult spelling. Collect responses as students leave.

Resources

• the spelling detectives slide deck
• the suffix spelling practice sheet
• Whiteboard and markers
• Exercise books or lined paper
• Pens, pencils and highlighters
• Projector or interactive display
• Word-family reference dictionaries, if available

Assessment

• Listen during partner noticing and group sorting for accurate identification of base words, suffixes, and spelling changes.
• Check worksheet responses, particularly whether students can distinguish vowel changes from consonant changes and explain their thinking.
• Use the exit check to identify students needing further practice with word families, ambiguous spellings, or suffixes.

Differentiation

• Support students with a word bank containing the base words, suffixes, and completed examples. Allow them to rehearse words orally before writing.
• Pair students strategically and provide the sentence stem: “The base word is ____. When I add ____, the spelling changes by ____.”
• For students with dyslexia or other literacy needs, use a clear sans-serif font, generous spacing, reduced copying, and access to a text-to-speech or spelling tool where appropriate.
• Extend confident spellers by asking them to find another word in the same family, explain whether the pattern transfers, and write a sentence using both forms.