Before you start
- 12 original KJSEA Integrated Science questions, 40 marks, 55 minutes, written in the style of the structured questions in paper 905/1.
- They cover all four strands of Grade 7 to 9 Integrated Science: Scientific Investigation; Mixtures, Elements and Compounds; Living Things and Their Environment; and Force and Energy.
- Every question has a marking guide showing exactly which points earn the marks, plus "also accept" answers and the mistakes markers see most.
- The real papers: 905/1 on Thursday 29 October 2026 at 8.30 a.m. and 905/2 on Friday 30 October at 2.00 p.m.
Most searches for "KJSEA 2026 papers with answers PDF" end in one of two places: a question paper with no marking scheme, which is no use to a parent who is not a science teacher, or a "leaked paper" that is always fake. This page gives you something you can actually use tonight: twelve original Grade 9 Integrated Science questions, a time limit, and a marking guide for every one, so your child can sit them and you can mark them fairly.
These are original practice questions written by CBC Edu Kenya, not KNEC questions and not a leaked paper. If you want to know how the subject is examined first, read what KJSEA Integrated Science actually assesses, and for the practical-based paper see our 905/2 practical paper guide. This page is the practice.
How to use these questions
| Step | What to do |
|---|---|
| 1. Set the clock | 55 minutes for 40 marks, close to the pace of the real 905/1 paper (70 marks in 1 hour 40 minutes). |
| 2. Answer on paper | Blue or black pen. Show working for every calculation, with units. |
| 3. Count the marks | A 3-mark question needs three separate points. One long sentence usually earns one mark. |
| 4. Mark honestly | Use the marking guide. Give a mark only when the key word or idea is there. |
| 5. Find the strand | Use the answer table at the end to see which strand lost the marks, and revise that first. |
KJSEA Integrated Science sample questions
CBC EDU KENYA: KJSEA 2026 INTEGRATED SCIENCE SAMPLE QUESTIONS
Grade 9 · Time: 55 minutes · 40 marks · Answer ALL questions. Where needed, take g = 10 N/kg.
1. Akinyi finds the mass of a small stone to be 78 g. She pours water into a measuring cylinder to the 40.0 cm3 mark, lowers the stone in, and the level rises to 70.0 cm3.
(a) Name the method she used to find the volume of the stone. (1 mark)
(b) State the volume of the stone. (1 mark)
(c) Calculate the density of the stone. (1 mark)
2. Baraka heats some water in a test tube over a Bunsen burner. He fills the test tube to the brim, holds it with his bare fingers, and points its mouth towards Amina, who is standing beside him. State three mistakes Baraka made and the correct practice for each. (3 marks)
3. Mwangi is given a mixture of sand, common salt and water. Describe how he can obtain dry salt from the mixture, naming the residue and the filtrate. (3 marks)
4. The table shows the pH values of four solutions.
| Solution | A: lemon juice | B: distilled water | C: milk of magnesia | D: sodium hydroxide solution |
|---|---|---|---|---|
| pH | 2 | 7 | 10 | 13 |
(a) Which solution would turn blue litmus paper red? (1 mark)
(b) Which solution is neutral? (1 mark)
(c) Which solution would be used to relieve indigestion caused by excess stomach acid? Give a reason why D would not be used. (1 mark)
5. An atom of element X has atomic number 13 and mass number 27.
(a) How many neutrons does the atom have? (1 mark)
(b) Write the electron arrangement of X. (1 mark)
(c) State the period and group of X in the periodic table. (1 mark)
(d) Write the formula of the ion X forms and state how many electrons the ion has. (1 mark)
6. Element Z has electron arrangement 2,8,1 and element Y has electron arrangement 2,8,7. They react to form a compound.
(a) Name the type of bond formed. (1 mark)
(b) Explain how the bond forms. (1 mark)
(c) State one property of the compound formed. (1 mark)
7. (a) Name two structures found in a plant cell that are not found in an animal cell. (2 marks)
(b) State the function of the chloroplast. (1 mark)
8. Fatuma cut two potato strips, each 5.0 cm long. She placed one in distilled water and the other in a concentrated salt solution. After 45 minutes the strip in water was 5.4 cm long and firm; the strip in salt solution was 4.6 cm long and soft.
(a) Name the process responsible for these changes. (1 mark)
(b) Explain why the strip in salt solution became shorter and soft. (1 mark)
(c) Explain why the strip in distilled water became longer and firm. (1 mark)
9. In testing a green leaf for starch, the leaf is first boiled in water, then boiled in ethanol placed in a hot water bath, then rinsed and iodine solution is added.
(a) Why is the leaf boiled in water? (1 mark)
(b) Why is the leaf boiled in ethanol? (1 mark)
(c) State the colour seen if starch is present. (1 mark)
10. In pea plants the allele for tall stems (T) is dominant over the allele for short stems (t). A heterozygous tall plant is crossed with a short plant.
(a) Give the gametes of each parent. (1 mark)
(b) Use a Punnett square to show the genotypes of the offspring. (1 mark)
(c) State the ratio of tall to short offspring. (1 mark)
(d) If 120 seeds from this cross grow, how many would you expect to be tall? (1 mark)
11. A boda boda starts from rest and reaches a speed of 15 m/s in 5 seconds. It then moves at a constant 15 m/s for a further 10 seconds. The mass of the motorcycle and rider is 250 kg.
(a) Calculate the acceleration in the first 5 seconds. (1 mark)
(b) Calculate the total distance travelled in the 15 seconds. (2 marks)
(c) Calculate the resultant force needed to produce the acceleration in (a). (1 mark)
12. A pulley system with a velocity ratio of 4 is used to lift a load of 600 N through a height of 2 m. The effort needed is 200 N.
(a) Calculate the mechanical advantage. (1 mark)
(b) Calculate the efficiency of the system. (1 mark)
(c) Calculate the work done on the load. (1 mark)
(d) Calculate the work done by the effort. (1 mark)
Original practice items prepared by CBC Edu Kenya. Not an official KNEC paper and not a leaked paper. cbcedukenya.com
Stop here until the 55 minutes are up. The marking guide starts below.
Marking guide with answers
Each tick below is one mark. Give the mark when the key idea is there in the learner's own words; the exact wording does not have to match. In calculations, give the mark only when the unit is correct as well.
Question 1: measurement and density (Scientific Investigation, Grade 7)
(a) Displacement method (displacement of water). ✓
(b) Volume = 70.0 − 40.0 = 30.0 cm3. ✓
(c) Density = mass ÷ volume = 78 ÷ 30 = 2.6 g/cm3. ✓ (Also accept 2,600 kg/m3.)
Where marks are lost: using 70 cm3 as the volume, or giving a density with no unit.
Question 2: laboratory safety (Scientific Investigation, Grade 7)
Any three, one mark each when both the mistake and the correction are given:
Filled the test tube to the brim; it should be filled to about a third or less so the boiling water does not spill out. ✓
Held the test tube with bare fingers; he should use a test-tube holder. ✓
Pointed the mouth at Amina; it should point away from himself and from other people. ✓
(Also accept: not heating gently and moving the tube in the flame, so the liquid does not shoot out.)
Question 3: separating a mixture (Mixtures, Elements and Compounds, Grade 7)
Stir so that all the salt dissolves in the water, then filter. ✓
Sand remains on the filter paper as the residue; the salt solution passes through as the filtrate. ✓
Heat the filtrate in an evaporating dish until the water evaporates and dry salt remains (or heat until crystals begin to form, then leave to dry). ✓
Where marks are lost: calling the salt solution the residue, or trying to separate the salt with a magnet or by decanting.
Question 4: acids, bases and indicators (Mixtures, Elements and Compounds, Grade 7)
(a) A (lemon juice, pH 2, is acidic). ✓
(b) B (distilled water, pH 7). ✓
(c) C, milk of magnesia, a weak base (alkali) that neutralises the excess acid; D is a strong alkali that is corrosive and would burn the mouth and gut. ✓ (Both parts needed for the mark.)
Question 5: structure of the atom and the periodic table (Grade 9)
(a) Neutrons = mass number − atomic number = 27 − 13 = 14. ✓
(b) 2,8,3. ✓
(c) Period 3 (three shells), group 3, also written group III (three outer electrons). ✓ (Both needed.)
(d) X3+, with 10 electrons (it loses its three outer electrons; the 13 protons do not change). ✓
Where marks are lost: adding 27 + 13 for neutrons, or giving the ion 13 electrons.
Question 6: chemical bonding (Grade 9)
(a) Ionic bond. ✓
(b) Z loses its one outer electron to become Z+; Y gains that electron to become Y−; the oppositely charged ions attract each other. ✓
(c) Any one: high melting point; conducts electricity when molten or dissolved in water (not when solid); soluble in water; crystalline solid at room temperature. ✓
Where marks are lost: saying the atoms "share" electrons, which describes covalent bonding.
Question 7: the cell (Living Things and Their Environment, Grade 8)
(a) Any two: cell wall ✓; chloroplast ✓; large permanent (sap) vacuole.
(b) It contains chlorophyll, which traps (absorbs) light energy for photosynthesis. ✓
Where marks are lost: naming the cell membrane, nucleus or cytoplasm, which animal cells also have.
Question 8: osmosis (Living Things and Their Environment, Grade 8)
(a) Osmosis. ✓
(b) The salt solution is more concentrated than the cell sap, so water moved out of the potato cells by osmosis; the cells became flaccid, so the strip shrank and went soft. ✓
(c) The cell sap is more concentrated than distilled water, so water moved into the cells by osmosis; the cells became turgid, so the strip lengthened and became firm. ✓
Where marks are lost: saying "salt moved into the potato", or not saying which way the water moved.
Question 9: testing a leaf for starch (Nutrition in Plants, Grade 8)
(a) To kill the cells and break down the cell membranes so that iodine can enter (also accept: to stop chemical reactions in the leaf). ✓
(b) To remove the chlorophyll (decolourise the leaf) so that the colour change with iodine can be seen. ✓
(c) Blue-black. ✓ (The iodine stays brown where there is no starch.)
Marker's note: the ethanol is heated in a water bath, not over a naked flame, because ethanol is highly flammable. A question may ask this for a mark.
Question 10: genetics (Grade 9)
(a) Heterozygous tall parent (Tt): gametes T and t. Short parent (tt): gametes t and t. ✓
(b) Punnett square:
| Gametes | T | t |
|---|---|---|
| t | Tt | tt |
| t | Tt | tt |
Genotypes: 2 Tt and 2 tt. ✓
(c) Tall : short = 1 : 1. ✓
(d) Half are expected to be tall: 1/2 × 120 = 60. ✓
Where marks are lost: writing 3 : 1, which is the ratio for Tt × Tt, not Tt × tt.
Question 11: motion (Force and Energy, Grade 9)
(a) Acceleration = change in velocity ÷ time = (15 − 0) ÷ 5 = 3 m/s2. ✓
(b) Distance = area under the speed-time graph.
First 5 s (triangle): ½ × 5 × 15 = 37.5 m; next 10 s (rectangle): 10 × 15 = 150 m. ✓
Total = 37.5 + 150 = 187.5 m. ✓
(c) F = ma = 250 × 3 = 750 N. ✓
Where marks are lost: using 15 m/s × 15 s = 225 m, which ignores the speeding-up phase; writing m/s for acceleration.
Question 12: machines, work and efficiency (Force and Energy, Grade 9)
(a) MA = load ÷ effort = 600 ÷ 200 = 3 (no unit). ✓
(b) Efficiency = MA ÷ VR × 100% = 3 ÷ 4 × 100 = 75%. ✓
(c) Work on the load = 600 N × 2 m = 1,200 J. ✓
(d) The effort moves VR × load distance = 4 × 2 = 8 m, so work by the effort = 200 N × 8 m = 1,600 J. ✓
Check: 1,200 ÷ 1,600 × 100 = 75%, the same efficiency as in (b). The missing 400 J is wasted against friction and in lifting the moving pulleys.
Answer table (print this for marking)
| Q | Strand and sub-strand | Key answers | Marks |
|---|---|---|---|
| 1 | Scientific Investigation: measurement | Displacement; 30.0 cm3; 2.6 g/cm3 | 3 |
| 2 | Scientific Investigation: laboratory safety | Fill a third; use a holder; point away from people | 3 |
| 3 | Mixtures: separation | Dissolve and filter; sand residue, salt solution filtrate; evaporate | 3 |
| 4 | Mixtures: acids, bases and indicators | A; B; C (weak base), D is corrosive | 3 |
| 5 | Structure of the atom; periodic table | 14; 2,8,3; period 3, group 3; X3+ with 10 electrons | 4 |
| 6 | Chemical bonding | Ionic; electron transfer, ions attract; high melting point | 3 |
| 7 | Living Things: the cell | Cell wall, chloroplast; traps light for photosynthesis | 3 |
| 8 | Living Things: movement of materials | Osmosis; water out (flaccid); water in (turgid) | 3 |
| 9 | Living Things: nutrition in plants | Kill cells; remove chlorophyll; blue-black | 3 |
| 10 | Living Things: genetics | T, t and t, t; 2 Tt : 2 tt; 1 : 1; 60 | 4 |
| 11 | Force and Energy: motion | 3 m/s2; 187.5 m; 750 N | 4 |
| 12 | Force and Energy: machines | MA 3; 75%; 1,200 J; 1,600 J | 4 |
| Total | 40 | ||
Reading the result by strand
| Strand | Questions | Marks | If most of these marks were lost |
|---|---|---|---|
| Scientific Investigation | 1, 2 | 6 | Revise apparatus, units and safety; these skills also carry the 905/2 practical paper. |
| Mixtures, Elements and Compounds | 3 to 6 | 13 | Practise electron arrangements for the first 20 elements until they are automatic. |
| Living Things and Their Environment | 7 to 10 | 13 | Learn the reason for each step of the standard experiments, not just the steps. |
| Force and Energy | 11, 12 | 8 | Write the formula, substitute, then give the unit, every time. |
A learner who scored well in calculations but lost marks in Questions 7 to 9 usually knows the facts but writes one idea where the question wanted two. That is fixed by counting the marks and writing one point per mark, which is the single habit most worth drilling in the next four weeks.
Full KJSEA papers with answers for all nine learning areas
Twelve questions show the standard. For the final weeks a candidate needs full-length papers in every learning area, sat in the real KNEC time, and marked against a proper scheme. The KJSEA Complete Course gives your child, for all 9 learning areas:
- Full notes for Grades 7, 8 and 9, organised by strand and sub-strand, with worked examples and the mistakes that cost marks.
- Predictive papers in the KNEC paper codes and timings, including Integrated Science 905/1 and 905/2.
- Separate answer booklets, so papers are sat honestly first and marked afterwards.
It costs KSH 400 for all nine learning areas and downloads instantly after M-Pesa payment. Every paper is original practice material written by CBC Edu Kenya, not a KNEC paper and not a leaked one.
Get the KJSEA Complete Course: full notes, predictive papers and separate answer booklets for all 9 learning areas, KSH 400.
Frequently asked questions
When are the KJSEA 2026 Integrated Science papers?
905/1 is on Thursday 29 October 2026 from 8.30 a.m. to 10.10 a.m., and 905/2 (practical-based) is on Friday 30 October from 2.00 p.m. to 3.00 p.m. The whole week is on our KJSEA and KPSEA 2026 calendar, and the night-before plan is in the KJSEA timetable, paper by paper.
Can I download these questions as a PDF?
Yes: use your browser's print option and choose "Save as PDF". The questions, the marking guide and the answer table will all print.
Are these the actual KJSEA 2026 questions?
No. Nobody has the 2026 questions before the exam, and anyone selling them is running a scam. These are original questions that practise the sub-strands the curriculum emphasises. There is also a KJSEA 2026 Mathematics sample paper with answers in the same format.
Grade 9 KJSEA Complete Revision Course
All 9 learning areas in one download: notes, worked examples, topical questions and full marking schemes. Rebuilt for the 26 to 30 October assessment.
⏳ Only 25 days to the national assessments on 26 October. Start now.
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